Add requirement for newer libgssglue for svcgssd -n option

SNAFU.  This came to my attention minutes after 1.2.4 was
released...

Changes in commit d6c1b35c require that gss_acquire_cred()
is now called when the "-n" option is used.  This requires an
updated libgssglue which properly handles name GSS_C_NO_NAME
as input to gss_import_name()/gss_acquire_cred().

Add a requirement for the newer version.

Without the newer libgssglue, when svcgssd is started with "-n"
you will see the error message, "ERROR: GSS-API: error in
gss_acquire_cred(): GSS_S_BAD_NAME (An invalid name was supplied)
- Unknown error"

Signed-off-by: Steve Dickson <steved@redhat.com>