MIPS: simplify relocated _G_O_T_ address calculation

The difference between the address of the original
and the relocated _GLOBAL_OFFSET_TABLE_ is always
the same as the relocation offset.

The relocation offset is already computed and it is
available in the 's1/t6' register. Use that to adjust
the relocated _G_O_T_ address, instead of calculating
the offset again from the _gp value.

Signed-off-by: Gabor Juhos <juhosg@openwrt.org>
Cc: Daniel Schwierzeck <daniel.schwierzeck@googlemail.com>
Cc: Xiangfu Liu <xiangfu@openmobilefree.net>
diff --git a/arch/mips/cpu/xburst/start.S b/arch/mips/cpu/xburst/start.S
index 194d745..9e637df 100644
--- a/arch/mips/cpu/xburst/start.S
+++ b/arch/mips/cpu/xburst/start.S
@@ -122,7 +122,6 @@
 	jr	t0
 	 nop
 
-	.word	_gp
 	.word	_GLOBAL_OFFSET_TABLE_
 	.word	uboot_end_data
 	.word	uboot_end
@@ -137,9 +136,7 @@
 	 */
 	lw	t3, -4(t0)		# t3 <-- num_got_entries
 	lw	t4, -16(t0)		# t4 <-- _GLOBAL_OFFSET_TABLE_
-	lw	t5, -20(t0)		# t5 <-- _gp
-	sub	t4, t5			# compute offset
-	add	t4, t4, gp		# t4 now holds relocated _G_O_T_
+	add	t4, t6			# t4 now holds relocated _G_O_T_
 	addi	t4, t4, 8		# skipping first two entries
 	li	t2, 2
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