dpaa2: Extract frame-specific routines to dpaa2_frame.[h,c]

As soon as we need information from the hardware frame annotation to
make sure that checksums of the ingress frames were verified by the
DPAA2 HW, I've decided to make a preparation and extracted all of the
frame related routines into the separate dpaa2_frame.[h,c] along with
some clean up and improvements, e.g. no more dpaa2_fa, but dpaa2_swa
and dpaa2_hwa structures to describe software and hardware frame
annotations respectively, dpaa2_fa_get_swa/dpaa2_fa_get_hwa to obtain
those annotations from the frame descriptor. The next step is to
implement dpaa2_fa_get_hwa.

PR: 292006
Approved by: tuexen
MFC after: 1 week
Differential Revision: https://reviews.freebsd.org/D56315