tile: use proper .align directives on __ex_table sections

This may fix a reported bug where an R_TILEGX_64 in a module was not
pointing to an aligned address.

Reported-by: Simon Marchi <simon.marchi@polymtl.ca>
Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>

arch/tile/include/asm/futex.h

@@ -43,6 +43,7 @@
 	    ".pushsection .fixup,\"ax\"\n"			\
 	    "0: { movei %0, %5; j 9f }\n"			\
 	    ".section __ex_table,\"a\"\n"			\
+	    ".align 8\n"					\
 	    ".quad 1b, 0b\n"					\
 	    ".popsection\n"					\
 	    "9:"						\