patch 8.1.1306: Borland support is outdated and doesn't work

Problem:    Borland support is outdated and doesn't work.
Solution:   Remove Borland support, there are other (free) compilers
            available. (Thomas Dziedzic, Ken Takata, closes #4364)
diff --git a/src/INSTALLpc.txt b/src/INSTALLpc.txt
index 0c276fa..c72875a 100644
--- a/src/INSTALLpc.txt
+++ b/src/INSTALLpc.txt
@@ -25,21 +25,20 @@
 2. Using MSYS2 with MinGW
 3. Using MinGW
 4. Cygwin
-5. Borland
-6. Cross compiling for Win32 from a Linux machine
-7. Building with Python support
-8. Building with Python3 support
-9. Building with Racket or MzScheme support
-10. Building with Lua support
-11. Building with Perl support
-12. Building with Ruby support
-13. Building with Tcl support
-14. Building with Terminal support
-15. Building with DirectX (DirectWrite) support
-16. Windows 3.1
-17. MS-DOS
+5. Cross compiling for Win32 from a Linux machine
+6. Building with Python support
+7. Building with Python3 support
+8. Building with Racket or MzScheme support
+9. Building with Lua support
+10. Building with Perl support
+11. Building with Ruby support
+12. Building with Tcl support
+13. Building with Terminal support
+14. Building with DirectX (DirectWrite) support
+15. Windows 3.1
+16. MS-DOS
 
-18. Installing after building from sources
+17. Installing after building from sources
 
 
 The currently recommended way (that means it has been verified to work) is
@@ -451,14 +450,7 @@
 with the other makefiles).
 
 
-5. Borland
-===========
-
-Use Make_bc5.mak with Borland C++ 5.x. See
-    http://users.skynet.be/antoine.mechelynck/vim/compile.htm
-
-
-6. Cross compiling for Win32 from a Linux machine
+5. Cross compiling for Win32 from a Linux machine
 =================================================
 
 [Update of 1) needs to be verified]
@@ -478,7 +470,7 @@
 Now you have created the Windows binary from your Linux box!  Have fun...
 
 
-7. Building with Python support
+6. Building with Python support
 ===============================
 
 For building with MSVC 2008 the "Windows Installer" from www.python.org
@@ -539,7 +531,7 @@
 You will end up with a Python-enabled, Win32 version. Enjoy!
 
 
-8. Building with Python3 support
+7. Building with Python3 support
 ================================
 
 For building with MSVC 2008 the "Windows Installer" from www.python.org
@@ -576,7 +568,7 @@
 libstdc++-6.dll.)
 
 
-9. Building with Racket or MzScheme support
+8. Building with Racket or MzScheme support
 ========================================
 
 1) Building with Racket support (newest)
@@ -666,7 +658,7 @@
 
 
 
-10. Building with Lua support
+9. Building with Lua support
 ============================
 
 Vim with Lua support can be built with either MSVC or MinGW (or maybe Cygwin).
@@ -721,7 +713,7 @@
         LUA=/cygdrive/c/projects/lua53 DYNAMIC_LUA=yes LUA_VER=53
 
 
-11. Building with Perl support
+10. Building with Perl support
 ==============================
 
 Vim with Perl support can be built with either MSVC or MinGW (or Cygwin).
@@ -747,7 +739,7 @@
         PERL=C:/Perl DYNAMIC_PERL=yes PERL_VER=522
 
 
-12. Building with Ruby support
+11. Building with Ruby support
 ==============================
 
 Vim with Ruby support can be built with either MSVC or MinGW (or Cygwin).
@@ -855,7 +847,7 @@
 
 
 
-13. Building with Tcl support
+12. Building with Tcl support
 =============================
 
 Vim with Tcl support can be built with either MSVC or MinGW (or Cygwin).
@@ -894,7 +886,7 @@
         TCL=C:/Tcl86 DYNAMIC_TCL=yes TCL_VER=86 TCL_VER_LONG=8.6
 
 
-14. Building with Terminal support
+13. Building with Terminal support
 ==================================
 
 Vim with Terminal support can be built with either MSVC, MinGW or Cygwin.
@@ -910,7 +902,7 @@
     mingw32-make -f Make_ming.mak TERMINAL=yes
 
 
-15. Building with DirectX (DirectWrite) support
+14. Building with DirectX (DirectWrite) support
 ===============================================
 
 Vim with DirectX (DirectWrite) support can be built with either MSVC or MinGW.
@@ -944,20 +936,20 @@
     mingw32-make -f Make_ming.mak DIRECTX=yes
 
 
-16. Windows 3.1x
+15. Windows 3.1x
 ================
 
 The Windows 3.1x support was removed in patch 7.4.1364.
 
 
-17. MS-DOS
+16. MS-DOS
 ==========
 
 The MS-DOS support was removed in patch 7.4.1399.  Only very old Vim versions
 work on MS-DOS because of the limited amount of memory available.
 
 
-18. Installing after building from sources
+17. Installing after building from sources
 ==========================================
 
 [provided by Michael Soyka, updated by Ken Takata]