[MIPS] Add __ucmpdi2 implementation

Recent GCC SVN versions may generate calls to __ucmpdi2.

Signed-off-by: Thiemo Seufer <ths@networkno.de>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

arch/mips/lib/Makefile

@@ -9,4 +9,4 @@ obj-y			+= iomap.o
 obj-$(CONFIG_PCI)	+= iomap-pci.o
 
 # libgcc-style stuff needed in the kernel
-lib-y += ashldi3.o ashrdi3.o lshrdi3.o
+lib-y += ashldi3.o ashrdi3.o lshrdi3.o ucmpdi2.o