patch 8.1.1306: Borland support is outdated and doesn't work

Problem:    Borland support is outdated and doesn't work.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/misc1.c b/src/misc1.c
index 3797094..a1c9a82 100644
--- a/src/misc1.c
+++ b/src/misc1.c
@@ -5626,18 +5626,11 @@
  * File name expansion code for MS-DOS, Win16 and Win32.  It's here because
  * it's shared between these systems.
  */
-# if defined(PROTO)
-#  define _cdecl
-# else
-#  ifdef __BORLANDC__
-#   define _cdecl _RTLENTRYF
-#  endif
-# endif
 
 /*
  * comparison function for qsort in dos_expandpath()
  */
-    static int _cdecl
+    static int
 pstrcmp(const void *a, const void *b)
 {
     return (pathcmp(*(char **)a, *(char **)b, -1));