qoriq / nxp: fix spelling in device_set_desc()

The product series is called NXP QorIQ Layerscape. Remove the extra 'e. [1]
Fix spelling of NXP, which is not NPX, in two places. [2]

Reviewed by: mmel, emaste [1]
Reported by: Kevin Bowling (kevin.bowling kev009.com), qoriq_dw_pci.c [2]
Differential Revision: https://reviews.freebsd.org/D55388

(cherry picked from commit a4e30909ec983f7986954e6c509ea21422561d84)
(cherry picked from commit c3ed2f3e414497ab3cf6ade17e52a87f07a547e6)