Replace .align with .balign to avoid ambiguity

Directive .align is arch-dependent, .balign is not.

Change-Id: Ibf2097da29f743f2c87c79d2a88ce1abd0aa6227
diff --git a/libpixelflinger/arch-mips/col32cb16blend.S b/libpixelflinger/arch-mips/col32cb16blend.S
index 57a6115..810294c 100644
--- a/libpixelflinger/arch-mips/col32cb16blend.S
+++ b/libpixelflinger/arch-mips/col32cb16blend.S
@@ -59,7 +59,7 @@
        .endm
 
        .text
-       .align 4
+       .balign 4
 
        .global scanline_col32cb16blend_mips
        .ent    scanline_col32cb16blend_mips