Staging: gdm724x: LTE: Refactor gdm_lte_pdn_table().

Mostly this change just reverses the primary conditional so most of
the code can be pulled back a tab, which fixes some code style
warnings.

Signed-off-by: Quytelda Kahja <quytelda@tamalin.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>