ARM: uniphier: delete unneeded input enable for low-level debug

The UART I/O ports for PH1-Pro4 has no input enable controlling.
This code is useless.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
diff --git a/arch/arm/mach-uniphier/ph1-pro4/lowlevel_debug.S b/arch/arm/mach-uniphier/ph1-pro4/lowlevel_debug.S
index 19bef2a..ce5dd4b 100644
--- a/arch/arm/mach-uniphier/ph1-pro4/lowlevel_debug.S
+++ b/arch/arm/mach-uniphier/ph1-pro4/lowlevel_debug.S
@@ -30,10 +30,5 @@
 		mov		r1, #1
 		str		r1, [r0]
 
-		ldr		r0, =SG_IECTRL
-		ldr		r1, [r0]
-		orr		r1, r1, #1
-		str		r1, [r0]
-
 		mov		pc, lr
 ENDPROC(setup_lowlevel_debug)