powerpc: mpc85xx: Rename _start_e500 symbol to _start

The real entry point is _start_e500. There is no _start symbol at all. So
rename _start_e500 to _start for convension that _start symbol is used as
entry point.

Signed-off-by: Pali Rohár <pali@kernel.org>
Reviewed-by: Priyanka Jain <priyanka.jain@nxp.com>
diff --git a/arch/powerpc/cpu/mpc85xx/start.S b/arch/powerpc/cpu/mpc85xx/start.S
index 07e855e..2b2ad97 100644
--- a/arch/powerpc/cpu/mpc85xx/start.S
+++ b/arch/powerpc/cpu/mpc85xx/start.S
@@ -70,9 +70,9 @@
  */
 
 	.section .bootpg,"ax"
-	.globl _start_e500
+	.globl _start
 
-_start_e500:
+_start:
 /* Enable debug exception */
 	li	r1,MSR_DE
 	mtmsr	r1