Update helgrind and drd suppression libc and libpthread paths in glibc 2.34
glibc 2.34 moved all pthread functions into the main libc library.
And it changed the (in memory) path of the main libc library to
libc.so.6 (before it was libc-2.xx.so).
This breaks various standard suppressions for helgrind and drd.
Fix this by doing a configure check for whether we are using glibc
2.34 by checking whether pthread_create is in libc instead of in
libpthread. If we are using glibc then define GLIBC_LIBC_PATH and
GLIBC_LIBPTHREAD_PATH variables that point to the (regexp) path
of the library that contains all libc functions and pthread functions
(which will be the same path for glibc 2.34+).
Rename glibc-2.34567-NPTL-helgrind.supp to glibc-2.X-helgrind.supp.in
and glibc-2.X-drd.supp to glibc-2.X-drd.supp.in and replace the
GLIBC_LIBC_PATH and GLIBC_LIBPTHREAD_PATH at configure time.
The same could be done for the glibc-2.X.supp.in file, but hasn't
yet because it looks like most suppressions in that file are obsolete.