mips: move CONFIG_MIPS{32, 64} definition to config.mk

All mips32 boards define CONFIG_MIPS32 in config headers
except malta boards which define it in boards.cfg.
We can consolidate them by defining it in
arch/mips/cpu/mips32/config.mk.

CONFIG_MIPS64 definition can be moved to
arch/mips/cpu/mips64/config.mk as well.

Signed-off-by: Masahiro Yamada <yamada.m@jp.panasonic.com>
Cc: Daniel Schwierzeck <daniel.schwierzeck@gmail.com>
Acked-by: Daniel Schwierzeck <daniel.schwierzeck@gmail.com>
diff --git a/arch/mips/cpu/mips32/config.mk b/arch/mips/cpu/mips32/config.mk
index cd4ce7a..332cd62 100644
--- a/arch/mips/cpu/mips32/config.mk
+++ b/arch/mips/cpu/mips32/config.mk
@@ -11,9 +11,7 @@
 # Note: Toolchains with binutils prior to v2.16
 # are no longer supported by U-Boot MIPS tree!
 #
-MIPSFLAGS := -march=mips32r2
-
-PLATFORM_CPPFLAGS += $(MIPSFLAGS)
+PLATFORM_CPPFLAGS += -DCONFIG_MIPS32 -march=mips32r2
 PLATFORM_CPPFLAGS += -mabi=32 -DCONFIG_32BIT
 ifdef CONFIG_SYS_BIG_ENDIAN
 PLATFORM_LDFLAGS  += -m elf32btsmip
diff --git a/arch/mips/cpu/mips64/config.mk b/arch/mips/cpu/mips64/config.mk
index 3c01136..c55eb7f 100644
--- a/arch/mips/cpu/mips64/config.mk
+++ b/arch/mips/cpu/mips64/config.mk
@@ -11,9 +11,7 @@
 # Note: Toolchains with binutils prior to v2.16
 # are no longer supported by U-Boot MIPS tree!
 #
-MIPSFLAGS = -march=mips64
-
-PLATFORM_CPPFLAGS += $(MIPSFLAGS)
+PLATFORM_CPPFLAGS += -DCONFIG_MIPS64 -march=mips64
 PLATFORM_CPPFLAGS += -mabi=64 -DCONFIG_64BIT
 ifdef CONFIG_SYS_BIG_ENDIAN
 PLATFORM_LDFLAGS  += -m elf64btsmip