firmware(9): extend firmware_get() by a "no warn" flag.
With the upcoming usage from LinuxKPI but also from drivers
ported natively we are seeing more probing of various
Add the ability to firmware(9) to silence the
"firmware image loading/registering errors" by adding a new
firmware_get_flags() functions extending firmware_get() and
taking a flags argument as firmware_put() already does.
Requested-by: zeising (for future LinuxKPI/DRM)
Sponsored-by: The FreeBSD Foundation
Sponsored-by: Rubicon Communications, LLC ("Netgate")
MFC after: 3 days
Differential Revision: https://reviews.freebsd.org/D27413
(cherry picked from commit 6f65b505468aa8cedc57235604bd8df540d42735)