MIPS: Remove cc-option checks for -march=octeon

Nowadays our minimal supported GCC/Clang all support -march=octeon.
Remove cc-option checks to simplify code.
Signed-off-by: Jiaxun Yang <jiaxun.yang@flygoat.com>
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>

arch/mips/Makefile

@@ -174,10 +174,7 @@ cflags-$(CONFIG_CPU_SB1)	+= $(call cc-option,-mno-mdmx)
 cflags-$(CONFIG_CPU_SB1)	+= $(call cc-option,-mno-mips3d)
 cflags-$(CONFIG_CPU_R10000)	+= $(call cc-option,-march=r10000,-march=r8000) \
 			-Wa,--trap
-cflags-$(CONFIG_CPU_CAVIUM_OCTEON) += $(call cc-option,-march=octeon) -Wa,--trap
-ifeq (,$(findstring march=octeon, $(cflags-$(CONFIG_CPU_CAVIUM_OCTEON))))
-cflags-$(CONFIG_CPU_CAVIUM_OCTEON) += -Wa,-march=octeon
-endif
+cflags-$(CONFIG_CPU_CAVIUM_OCTEON) += -march=octeon -Wa,--trap
 cflags-$(CONFIG_CAVIUM_CN63XXP1) += -Wa,-mfix-cn63xxp1
 cflags-$(CONFIG_CPU_BMIPS)	+= -march=mips32 -Wa,-mips32 -Wa,--trap