fixup! mingw (MSys1): enable support for perl regular expressions

It is absolutely unnecessary to carry any msysGit-specific patches
in our fork. msysGit is dead, long live Git for Windows.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>

Author: dscho

config.mak.uname

@@ -538,7 +538,6 @@ ifneq (,$(wildcard ../THIS_IS_MSYSGIT))
 	HAVE_LIBCHARSET_H = YesPlease
 	NO_GETTEXT = YesPlease
 	COMPAT_CLFAGS += -D__USE_MINGW_ACCESS
-	USE_LIBPCRE= YesPlease
 else
 	ifeq ($(shell expr "$(uname_R)" : '2\.'),2)
 		# MSys2