patch 8.1.0825: code for autocommands is mixed with file I/O code

Problem:    Code for autocommands is mixed with file I/O code.
Solution:   Move autocommand code to a separate file. (Yegappan Lakshmanan,
            closes #3863)
diff --git a/src/Make_manx.mak b/src/Make_manx.mak
index 04560d4..b71b923 100644
--- a/src/Make_manx.mak
+++ b/src/Make_manx.mak
@@ -37,6 +37,7 @@
 DEL = $(SHELL) -c rm -f
 
 SRC =	arabic.c \
+	autocmd.c \
 	blowfish.c \
 	buffer.c \
 	charset.c \
@@ -96,6 +97,7 @@
 INCL = vim.h feature.h keymap.h macros.h ascii.h term.h structs.h os_amiga.h
 
 OBJ =	obj/arabic.o \
+	obj/autocmd.o \
 	obj/blowfish.o \
 	obj/buffer.o \
 	obj/charset.o \
@@ -153,6 +155,7 @@
 	$(TERMLIB)
 
 PRO =	proto/arabic.pro \
+	proto/autocmd.pro \
 	proto/blowfish.pro \
 	proto/buffer.pro \
 	proto/charset.pro \
@@ -256,6 +259,9 @@
 obj/arabic.o:	arabic.c
 	$(CCSYM) $@ arabic.c
 
+obj/autocmd.o:	autocmd.c
+	$(CCSYM) $@ autocmd.c
+
 obj/blowfish.o:	blowfish.c
 	$(CCSYM) $@ blowfish.c