Fix MIPS build.

Change-Id: I175f427e355fca9a5a3f4e4379d7fcd1f7f6a22d
diff --git a/libc/arch-mips/bionic/_exit_with_stack_teardown.S b/libc/arch-mips/bionic/_exit_with_stack_teardown.S
index ce05ab8..8f624c3 100644
--- a/libc/arch-mips/bionic/_exit_with_stack_teardown.S
+++ b/libc/arch-mips/bionic/_exit_with_stack_teardown.S
@@ -41,7 +41,7 @@
 	syscall
 	// If munmap failed, we ignore the failure and exit anyway.
 
-	move	$a0, 0
+	li	$a0, 0
 	li	$v0, __NR_exit
 	syscall
         // The exit syscall does not return.