parisc: Provide __ucmpdi2 to resolve undefined references in 32 bit builds.

The Debian experimental linux source package (3.8.5-1) build fails
with the following errors:
...
MODPOST 2016 modules
ERROR: "__ucmpdi2" [fs/btrfs/btrfs.ko] undefined!
ERROR: "__ucmpdi2" [drivers/md/dm-verity.ko] undefined!

The attached patch resolves this problem.  It is based on the s390
implementation of ucmpdi2.c.

Signed-off-by: John David Anglin <dave.anglin@bell.net>
Cc: "James E.J. Bottomley" <jejb@parisc-linux.org>
Signed-off-by: Helge Deller <deller@gmx.de>

arch/parisc/kernel/parisc_ksyms.c

@@ -120,11 +120,13 @@ extern void __ashrdi3(void);
 extern void __ashldi3(void);
 extern void __lshrdi3(void);
 extern void __muldi3(void);
+extern void __ucmpdi2(void);
 
 EXPORT_SYMBOL(__ashrdi3);
 EXPORT_SYMBOL(__ashldi3);
 EXPORT_SYMBOL(__lshrdi3);
 EXPORT_SYMBOL(__muldi3);
+EXPORT_SYMBOL(__ucmpdi2);
 
 asmlinkage void * __canonicalize_funcptr_for_compare(void *);
 EXPORT_SYMBOL(__canonicalize_funcptr_for_compare);