don't optimize for special mips cpu

When building optimized code for Lemote Yeelong system, a conflict
occurs. Better use optimized flags in your buildsystem, not in uClibc-ng.

Rules.mak

@@ -404,14 +404,6 @@ endif
 
 ifeq ($(TARGET_ARCH),mips)
 	OPTIMIZATION+=-mno-split-addresses
-	CPU_CFLAGS-$(CONFIG_MIPS_ISA_1)+=-mips1
-	CPU_CFLAGS-$(CONFIG_MIPS_ISA_2)+=-mips2 -mtune=mips2
-	CPU_CFLAGS-$(CONFIG_MIPS_ISA_3)+=-mips3 -mtune=mips3
-	CPU_CFLAGS-$(CONFIG_MIPS_ISA_4)+=-mips4 -mtune=mips4
-	CPU_CFLAGS-$(CONFIG_MIPS_ISA_MIPS32)+=-mips32 -mtune=mips32
-	CPU_CFLAGS-$(CONFIG_MIPS_ISA_MIPS32R2)+=-march=mips32r2 -mtune=mips32r2
-	CPU_CFLAGS-$(CONFIG_MIPS_ISA_MIPS64)+=-mips64 -mtune=mips32
-	CPU_CFLAGS-$(CONFIG_MIPS_ISA_MIPS64R2)+=-mips64r2 -mtune=mips64r2
 	ifeq ($(strip $(ARCH_BIG_ENDIAN)),y)
 		CPU_LDFLAGS-$(CONFIG_MIPS_N64_ABI)+=-Wl,-melf64btsmip
 		CPU_LDFLAGS-$(CONFIG_MIPS_O32_ABI)+=-Wl,-melf32btsmip