Replace --enable-static-pie with --disable-default-pie

Build glibc programs and tests as PIE by default and enable static-pie
automatically if the architecture and toolchain supports it.

Also add a new configuration option --disable-default-pie to prevent
building programs as PIE.

Only the following architectures now have PIE disabled by default
because they do not work at the moment.  hppa, ia64, alpha and csky
don't work because the linker is unable to handle a pcrel relocation
generated from PIE objects.  The microblaze compiler is currently
failing with an ICE.  GNU hurd tries to enable static-pie, which does
not work and hence fails.  All these targets have default PIE disabled
at the moment and I have left it to the target maintainers to enable PIE
on their targets.

build-many-glibcs runs clean for all targets.  I also tested x86_64 on
Fedora and Ubuntu, to verify that the default build as well as
--disable-default-pie work as expected with both system toolchains.

Signed-off-by: Siddhesh Poyarekar <siddhesh@sourceware.org>
Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>