MIPS: asm: stackframe: Do not preserve the HI/LO registers on MIPS R6

The HI/LO registers have been removed from MIPS R6. Instructions
such as MULT and DIV have been replaced with a new pair of
instructions for the HI/LO operations for example:

MULT -> MUL, MUH
DIV -> DIV, MOD

So we avoid preserving the pre-R6 HI/LO registers in MIPS R6

Signed-off-by: Leonid Yegoshin <Leonid.Yegoshin@imgtec.com>
Signed-off-by: Markos Chandras <markos.chandras@imgtec.com>

arch/mips/include/asm/stackframe.h

@@ -40,7 +40,7 @@
 		LONG_S	v1, PT_HI(sp)
 		mflhxu	v1
 		LONG_S	v1, PT_ACX(sp)
-#else
+#elif !defined(CONFIG_CPU_MIPSR6)
 		mfhi	v1
 #endif
 #ifdef CONFIG_32BIT
@@ -50,7 +50,7 @@
 		LONG_S	$10, PT_R10(sp)
 		LONG_S	$11, PT_R11(sp)
 		LONG_S	$12, PT_R12(sp)
-#ifndef CONFIG_CPU_HAS_SMARTMIPS
+#if !defined(CONFIG_CPU_HAS_SMARTMIPS) && !defined(CONFIG_CPU_MIPSR6)
 		LONG_S	v1, PT_HI(sp)
 		mflo	v1
 #endif
@@ -58,7 +58,7 @@
 		LONG_S	$14, PT_R14(sp)
 		LONG_S	$15, PT_R15(sp)
 		LONG_S	$24, PT_R24(sp)
-#ifndef CONFIG_CPU_HAS_SMARTMIPS
+#if !defined(CONFIG_CPU_HAS_SMARTMIPS) && !defined(CONFIG_CPU_MIPSR6)
 		LONG_S	v1, PT_LO(sp)
 #endif
 #ifdef CONFIG_CPU_CAVIUM_OCTEON
@@ -226,7 +226,7 @@
 		mtlhx	$24
 		LONG_L	$24, PT_LO(sp)
 		mtlhx	$24
-#else
+#elif !defined(CONFIG_CPU_MIPSR6)
 		LONG_L	$24, PT_LO(sp)
 		mtlo	$24
 		LONG_L	$24, PT_HI(sp)