Touch up some of the autotools files

Signed-off-by: Mike Frysinger <vapier@gentoo.org>
Signed-off-by: Kevin Coffman <kwc@citi.umich.edu>
this patch touches up the autotool code a bit in nfs-utils:
 - run autogen.sh with -e so if something fails, it'll abort properly
 - set ACLOCAL_AMFLAGS so that when running autoreconf or when
   autotools re-runs itself, the m4 files are found properly
 - make sure we include bsdsignals.m4 in the final tarball
 - add some cross-compiling fallback logic to bsdsignals.m4 so that
   when cross-compiling nfs-utils, the configure is a bit more nice
   than simply:
      checking for BSD signal semantics... configure: error: cannot run test program while cross compiling
Signed-off-by: Neil Brown <neilb@suse.de>