sh: Use -m2a-nofpu only

Based on reading over the GCC manual, passing both -m2a and -m2a-nofpu
are redundant, as -m2a-nofpu will provide functional code for both.  As
-m2a-nofpu functions with more toolchains and does what is expected,
switch.

Cc: Nobuhiro Iwamatsu <iwamatsu@nigauri.org>
Signed-off-by: Tom Rini <trini@konsulko.com>

arch/sh/cpu/sh2/config.mk

@@ -8,7 +8,7 @@
 ENDIANNESS += -EB
 
 ifdef CONFIG_CPU_SH2A
-PLATFORM_CPPFLAGS += -m2a -m2a-nofpu -mb
+PLATFORM_CPPFLAGS += -m2a-nofpu -mb
 else # SH2
 PLATFORM_CPPFLAGS += -m3e -mb
 endif