arm: Add ENTRY/ENDPROC to private libgcc functions

When CONFIG_SYS_THUMB_BUILD is defined these functions may be called from
Thumb code. Add the required ENTRY and ENDPROC bracketing so that BLX is
used to call these ARM functions, instead of plain BL, which will fail.

Signed-off-by: Simon Glass <sjg@chromium.org>
Reported-by: Pavel Machek <pavel@denx.de>
diff --git a/arch/arm/lib/_modsi3.S b/arch/arm/lib/_modsi3.S
index 3d31a55..c5e1c22 100644
--- a/arch/arm/lib/_modsi3.S
+++ b/arch/arm/lib/_modsi3.S
@@ -1,3 +1,5 @@
+#include <linux/linkage.h>
+
 .macro ARM_MOD_BODY dividend, divisor, order, spare
 
 #if __LINUX_ARM_ARCH__ >= 5
@@ -69,8 +71,7 @@
 .endm
 
 	.align	5
-.globl __modsi3
-__modsi3:
+ENTRY(__modsi3)
 	cmp	r1, #0
 	beq	Ldiv0
 	rsbmi	r1, r1, #0			@ loops below use unsigned.
@@ -88,7 +89,7 @@
 10:	cmp	ip, #0
 	rsbmi	r0, r0, #0
 	mov	pc, lr
-
+ENDPROC(__modsi3)
 
 Ldiv0: