sparc32: fix sparse warning in fault_32.c

Fix following warning:
fault_32.c:38:24: error: symbol 'unhandled_fault' redeclared with different type - different modifiers

When this warning was fixed several new warnings popped up - fix them too.

Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
Signed-off-by: David S. Miller <davem@davemloft.net>