linux-user/mips: fix abort on integer overflow

linux-user/mips: fix abort on integer overflow

QEMU mips userspace emulation crashes with "qemu: unhandled CPU exception
0x15 - aborting" when one of the integer arithmetic instructions detects
an overflow.

This patch fixes it so that it delivers SIGFPE with FPE_INTOVF instead.

Cc: qemu-stable@nongnu.org
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Message-Id: <3ef979a8-3ee1-eb2d-71f7-d788ff88dd11@redhat.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>