Cygwin 1.7 supports mmap

git has shipped for years with MMAP enabled in the stock distribution,
there are no reports of problems / failures on the list relating to
this. Leave the default as-is on v1.5 due to lack of knowlege of this
working on earlier Cygwin.

Signed-off-by: Mark Levedahl <mlevedahl@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

config.mak.uname

@@ -160,17 +160,17 @@ ifeq ($(uname_O),Cygwin)
 		NO_IPV6 = YesPlease
 		OLD_ICONV = UnfortunatelyYes
 		NO_THREAD_SAFE_PREAD = YesPlease
+		# There are conflicting reports about this.
+		# On some boxes NO_MMAP is needed, and not so elsewhere.
+		# Try commenting this out if you suspect MMAP is more efficient
+		NO_MMAP = YesPlease
 	else
 		NO_REGEX = UnfortunatelyYes
 	endif
 	NEEDS_LIBICONV = YesPlease
 	NO_FAST_WORKING_DIRECTORY = UnfortunatelyYes
 	NO_TRUSTABLE_FILEMODE = UnfortunatelyYes
 	NO_ST_BLOCKS_IN_STRUCT_STAT = YesPlease
-	# There are conflicting reports about this.
-	# On some boxes NO_MMAP is needed, and not so elsewhere.
-	# Try commenting this out if you suspect MMAP is more efficient
-	NO_MMAP = YesPlease
 	X = .exe
 	COMPAT_OBJS += compat/cygwin.o
 	UNRELIABLE_FSTAT = UnfortunatelyYes