Define _addr_lsb in siginfo_t for mips

Define an _addr_lsb field in the mips and ia64 siginfo_ts, following
the asm-generic version. This just puts the field over padding.

This fixes a compilation problem introduced with a337fdac.

Cc: ralf@linux-mips.org
Cc: tony.luck@intel.com
Signed-off-by: NAndi Kleen <ak@linux.intel.com>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

arch/mips/include/asm/siginfo.h

@@ -88,6 +88,7 @@ typedef struct siginfo {
 #ifdef __ARCH_SI_TRAPNO
 			int _trapno;	/* TRAP # which caused the signal */
 #endif
+			short _addr_lsb;
 		} _sigfault;
 
 		/* SIGPOLL, SIGXFSZ (To do ...)  */