Don't set CC in config/i386/go32.mh

I cross-compile gdb for msdosdjgpp (both target and host is
i586-pc-msdosdjgpp), so the CC should be i586-pc-msdosdjgpp-gcc.
However, CC is set incorrectly to gcc after config/i386/go32.mh is inlined
into the Makefile.

This patch is to remove the CC setting in config/i386/go32.mh.

gdb:

2014-11-19  Yao Qi  <yao@codesourcery.com>

	* config/i386/go32.mh (CC): Remove.

gdb/ChangeLog

@@ -1,3 +1,7 @@
+2014-11-19  Yao Qi  <yao@codesourcery.com>
+
+	* config/i386/go32.mh (CC): Remove.
+
 2014-11-18  Doug Evans  <xdje42@gmail.com>
 
 	* symtab.h (SYMTAB_BLOCKVECTOR): Renamed from BLOCKVECTOR.  All uses

gdb/config/i386/go32.mh

@@ -6,7 +6,6 @@ MH_CFLAGS= -I$(srcdir)/config/djgpp
 NATDEPFILES= go32-nat.o x86-nat.o x86-dregs.o
 
 HOST_IPC=
-CC= gcc
 XM_CLIBS= -ldbg