Remove LLVM_CONFIG from Makefile.global.in

LLVM_CONFIG is only used inside configure.

Reviewed-By: Peter Eisentraut <peter.eisentraut@enterprisedb.com>
Discussion: https://postgr.es/m/0e81e45c-c9a5-e95b-2782-ab2dfec8bf57@enterprisedb.com

Author: anarazel

src/Makefile.global.in

@@ -226,7 +226,6 @@ TCL_SHLIB_LD_LIBS	= @TCL_SHLIB_LD_LIBS@
 PTHREAD_CFLAGS		= @PTHREAD_CFLAGS@
 PTHREAD_LIBS		= @PTHREAD_LIBS@
 
-LLVM_CONFIG = @LLVM_CONFIG@
 LLVM_BINPATH = @LLVM_BINPATH@
 CLANG = @CLANG@
 BITCODE_CFLAGS = @BITCODE_CFLAGS@