[SH, 4.7] Backport Fix sh64-elf build failure [3/3]

[Oleg Endo]

Original patch:
http://gcc.gnu.org/ml/gcc-patches/2012-03/msg00210.html

'Tested' with..

../gcc-4_7-branch/configure --target=sh-elf --prefix=/usr/local
--enable-languages=c,c++ --enable-multilib --disable-libssp
--disable-nls --disable-werror --enable-lto --with-newlib --with-gnu-as
--with-gnu-ld --with-system-zlib

make all

OK for 4.7 branch?

ChangeLog:

        Backport from mainline
        2012-03-03  Kaz Kojima  <kkoj...@gcc.gnu.org>
        * config/sh/sh.md (abssi2): Add TARGET_SH1 condition.