[runtime] Make sure the stack is correctly aligned to 16 bytes.

runtime/trampolines-i386-objc_msgSend-post.inc

@@ -1,6 +1,6 @@
 Lafterinvoke:
 	addl	-16(%ebp), %esp
-	addl	$96, %esp
+	addl	$108, %esp
 	popl	%ebx
 	popl	%edi
 	popl	%esi

runtime/trampolines-i386-objc_msgSend-pre.inc

@@ -20,7 +20,7 @@ Lfunc_begin0:
 	# we need 64 bytes to store xmm0-3, and those 64 bytes need to be 16-byte aligned.
 	# we need 4 bytes to store the result for get_frame_length, which we store in %ebp-16
 	# then 4 more bytes for stack space for the call to get_frame_length (which takes 2 arguments)
-	subl	$96, %esp # to store xmm0-3
+	subl	$108, %esp # to store xmm0-3
 	movaps	%xmm0, -40(%ebp)
 	movaps	%xmm1, -56(%ebp)
 	movaps	%xmm2, -72(%ebp)