exec-all.h: Use stl_le_p instead of stl_p patching x86

We got the wrong version of stl_p, the one that bswaps as appropriate
for the target.  Since x86 is always little-endian, the "_le_" routine
will resolve to what we want.

Signed-off-by: Richard Henderson <rth@twiddle.net>
Merge remote-tracking branch 'remotes/rth/fix-i386' into staging

* remotes/rth/fix-i386:
  exec-all.h: Use stl_le_p instead of stl_p patching x86

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>