Replace .align with .balign for clarity

Test: run bionic-unit-tests
Change-Id: Icb43cc47e41d58fe3cb71986e05b3134022f895c
diff --git a/linker/arch/mips/begin.S b/linker/arch/mips/begin.S
index cbe1e37..1bdd358 100644
--- a/linker/arch/mips/begin.S
+++ b/linker/arch/mips/begin.S
@@ -27,7 +27,7 @@
  */
 
     .text
-    .align    4
+    .balign   16
     .type    __start,@function
 
     .ent    __start