Move the workaround out of linux-user/elfload.c, so that
we don't have to replicate it in many places. Place it
immediately after the include of <signal.h>, which draws
in the relevant symbols.
Note that ARCH_DLINFO is not defined by the kernel header,
and so there's no need to undef it either.
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>