Fix git-p4 on Windows to not use the Posix sysconf function.

Add condition for Windows, since it doesn't support the os.sysconf module.
We hardcode the commandline limit to 2K, as that should work on most
Windows platforms.

Signed-off-by: Marius Storm-Olsen <marius@trolltech.com>
Acked-by: Simon Hausmann <simon@lst.de>
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>

contrib/fast-import/git-p4

@@ -717,7 +717,11 @@ class P4Sync(Command):
         # POSIX says it's 4096 bytes, default for Linux seems to be 130 K.
         # and all OS from the table below seems to be higher than POSIX.
         # See http://www.in-ulm.de/~mascheck/various/argmax/
-        argmax = min(4000, os.sysconf('SC_ARG_MAX'))
+        if (self.isWindows):
+            argmax = 2000
+        else:
+            argmax = min(4000, os.sysconf('SC_ARG_MAX'))
+
         chunk = ''
         filedata = []
         for i in xrange(len(files)):