Revert "TlsAuthConfigDxe: fix TlsCaCertificate attributes retrieval"

Revert "TlsAuthConfigDxe: fix TlsCaCertificate attributes retrieval"

This reverts commit 6896efdec2709e530b23c688cf0f31706709a0c5.

REF:https://bugzilla.tianocore.org/show_bug.cgi?id=2062

GetVariable() now returns attributes when it fails with
EFI_BUFFER_TOO_SMALL. Therefore, commit 6896efdec270 is
reverted since it is no longer relevant.

Cc: Laszlo Ersek <lersek@redhat.com>
Cc: Siyuan Fu <siyuan.fu@intel.com>
Cc: Maciej Rabeda <maciej.rabeda@linux.intel.com>
Cc: Jiaxin Wu <jiaxin.wu@intel.com>
Signed-off-by: Michael Kubacki <michael.kubacki@microsoft.com>
Reviewed-by: Bret Barkelew <bret.barkelew@microsoft.com>
Reviewed-by: Laszlo Ersek <lersek@redhat.com>
Reviewed-by: Siyuan Fu <siyuan.fu@intel.com>