hppa: Remove _dl_skip_args usage (BZ# 29165)

Different than other architectures, hppa creates an unrelated stack
frame where ld.so argc/argv adjustments done by ad43cac4
is not done on the argc/argv saved/restore by _dl_start_user.

Instead load _dl_argc and _dl_argv directlty instead of adjust them
using _dl_skip_args value.

Checked on hppa-linux-gnu.

Reviewed-by: Carlos O'Donell <carlos@redhat.com>
(cherry picked from commit 62426022)