mingw: use MSys2's libgen.h

MSys2 actually *does* provide a libgen.h. Let's use it.

Signed-off-by: Johannes Schindelin <[email protected]>

Author: dscho

config.mak.uname

@@ -491,7 +491,6 @@ ifneq (,$(findstring MINGW,$(uname_S)))
 	HAVE_ALLOCA_H = YesPlease
 	NO_PREAD = YesPlease
 	NEEDS_CRYPTO_WITH_SSL = YesPlease
-	NO_LIBGEN_H = YesPlease
 	NO_POLL = YesPlease
 	NO_SYMLINK_HEAD = YesPlease
 	NO_UNIX_SOCKETS = YesPlease
@@ -543,6 +542,7 @@ ifneq (,$(wildcard ../THIS_IS_MSYSGIT))
 	HAVE_LIBCHARSET_H = YesPlease
 	NO_GETTEXT = YesPlease
 	COMPAT_CLFAGS += -D__USE_MINGW_ACCESS
+	NO_LIBGEN_H = YesPlease
 else
 	ifeq ($(shell expr "$(uname_R)" : '2\.'),2)
 		# MSys2
@@ -572,6 +572,7 @@ else
 	else
 		COMPAT_CFLAGS += -D__USE_MINGW_ANSI_STDIO
 		NO_CURL = YesPlease
+		NO_LIBGEN_H = YesPlease
 	endif
 endif
 endif