Fix typo.

Test/objc_msgSend.m

@@ -8,7 +8,7 @@
 id objc_msgSend(id, SEL, ...);
 
 typedef struct { int a,b,c,d,e; } s;
-s objc_msgSend_sret(id, SEL, ...);
+s objc_msgSend_stret(id, SEL, ...);
 
 Class TestCls;
 @interface Test { id isa; }@end
@@ -47,7 +47,7 @@ int main(void)
 	objc_registerSmallObjectClass_np(objc_getClass("Test"), 1);
 	a = objc_msgSend((id)01, @selector(foo));
 	assert((id)0x42 == a);
-	s ret = objc_msgSend_sret(TestCls, @selector(sret));
+	s ret = objc_msgSend_stret(TestCls, @selector(sret));
 	assert(ret.a == 1);
 	assert(ret.b == 2);
 	assert(ret.c == 3);

objc_msgSend.arm.S

@@ -85,9 +85,9 @@
 	.type	objc_msgSend, %function
 objc_msgSend:
 	MSGSEND r0, r1
-.globl objc_msgSend_sret
-	.type	objc_msgSend_sret, %function
-objc_msgSend_sret:
+.globl objc_msgSend_stret
+	.type	objc_msgSend_stret, %function
+objc_msgSend_stret:
 	MSGSEND r1, r2
 
 LSmallIntClass:

objc_msgSend.x86-32.S

@@ -83,7 +83,7 @@
 	.type	objc_msgSend, @function
 objc_msgSend:
 	MSGSEND 4, 8
-.globl objc_msgSend_sret
-	.type	objc_msgSend_sret, @function
-objc_msgSend_sret:
+.globl objc_msgSend_stret
+	.type	objc_msgSend_stret, @function
+objc_msgSend_stret:
 	MSGSEND 8, 12

objc_msgSend.x86-64.S

@@ -100,7 +100,7 @@
 	.type	objc_msgSend, @function
 objc_msgSend:
 	MSGSEND %rdi, %rsi
-.globl objc_msgSend_sret
-	.type	objc_msgSend_sret, @function
-objc_msgSend_sret:
+.globl objc_msgSend_stret
+	.type	objc_msgSend_stret, @function
+objc_msgSend_stret:
 	MSGSEND %rsi, %rdx