linux(4): Remove sys/cdefs.h inclusion where it's not needed due to 685dc743

sys: Remove $FreeBSD$: one-line .c pattern

Remove /^[\s*]*__FBSDID\("\$FreeBSD\$"\);?\s*\n/

sys: Remove $FreeBSD$: one-line .c comment pattern

Remove /^/[*/]\s*\$FreeBSD\$.*\n/

linux(4): Cleanup includes under compat/linux

Cleanup unneeded includes, sort the rest according to style(9).
No functional changes.

MFC after: 2 weeks

Add linux_to_bsd_errtbl[], mapping Linux errnos to their BSD counterparts.
This will be used by fuse(4).

Reviewed by: asomers
MFC after: 2 weeks
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D26974

Fix rookie mistake - it's nitems(), not sizeof().

Reported by: xtouqh_icloud.com
MFC after: 2 weeks
Sponsored by: The FreeBSD Foundation

Add defines for Linux errno values and use them to make linux_errtbl[]
more readable. While here, add linux_check_errtbl() function to make
sure we don't leave holes.

No objections: emaste (earlier version)
MFC after: 2 weeks
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D26972

Fix misnomer - linux_to_bsd_errno() does the exact opposite.

Reported by: arichardson
MFC after: 2 weeks
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D26965

Get rid of sv_errtbl and SV_ABI_ERRNO().

Reviewed by: kib
Sponsored by: DARPA
Differential Revision: https://reviews.freebsd.org/D26388

Share Linux errno table with libsysdecode

Requested by: jhb
Reviewed by: jhb
Sponsored by: Turing Robotic Industries Inc.

linux_errno.c: add newer errno values

Also introduce a static assert to ensure the list is kept up to date.

Sponsored by: Turing Robotic Industries Inc.

Share a single bsd-linux errno table across MD consumers

Three copies of the linuxulator linux_sysvec.c contained identical
BSD to Linux errno translation tables, and future work to support other
architectures will also use the same table. Move the table to a common
file to be used by all. Make it 'const int' to place it in .rodata.

(Some existing Linux architectures use MD errno values, but x86 and Arm
share the generic set.)

This change should introduce no functional change; a followup will add
missing errno values.

MFC after: 3 weeks
Sponsored by: Turing Robotic Industries Inc.
Differential Revision: https://reviews.freebsd.org/D14665