libc/glibc: both glibc and eglibc have pkgversion and bugurl

Well, all eglibc version we support do, and latest glibc versions
we support do.

Not all glibc versions do, but older versions simply ignore the
unrecognised ./configure flags.

Signed-off-by: "Yann E. MORIN" <yann.morin.1998@free.fr>

 # Compute Alpha-specific values

 CT_DoArchTupleValues () {

     # The architecture part of the tuple:

     CT_TARGET_ARCH="${CT_ARCH}${CT_ARCH_ALPHA_VARIANT}"

 }