remove sh port's __fpscr_values source file

commit f3ddd17380, the dynamic linker
bootstrap overhaul, silently disabled the definition of __fpscr_values
in this file since libc.so's copy of __fpscr_values now comes from
crt_arch.h, the same place the public definition in the main program's
crt1.o ultimately comes from. remove this file which is no longer in
use.

arch/sh/src/__fpscr_values.c

@@ -1,5 +0,0 @@
-#include "libc.h"
-
-/* used by gcc for switching the FPU between single and double precision */
-//const unsigned long __fpscr_values[2] ATTR_LIBC_VISIBILITY = { 0, 0x80000 };
-