Copy head (r256279) to stable/10 as part of the 10.0-RELEASE cycle.

Approved by: re (implicit)
Sponsored by: The FreeBSD Foundation

Remove redundant code.

Both mfi_flash.c and mfi_show.c contain very similar functions to print
a list of firmwares. Move these routines into mfiutil.c.

Reported by: jhb

More -Wmissing-variable-declarations fixes.

In addition to adding `static' where possible:

- bin/date: Move `retval' into extern.h to make it visible to date.c.
- bin/ed: Move globally used variables into ed.h.
- sbin/camcontrol: Move `verbose' into camcontrol.h and fix shadow warnings.
- usr.bin/calendar: Remove unneeded variables.
- usr.bin/chat: Make `line' local instead of global.
- usr.bin/elfdump: Comment out unneeded function.
- usr.bin/rlogin: Use _Noreturn instead of __dead2.
- usr.bin/tset: Pull `Ospeed' into extern.h.
- usr.sbin/mfiutil: Put global variables in mfiutil.h.
- usr.sbin/pkg: Remove unused `os_corres'.
- usr.sbin/quotaon, usr.sbin/repquota: Remove unused `qfname'.

Allow users with RO privilege to the device to read the RO attributes.

PR: bin/167302
Submitted by: markham breitbach <markham@ssimicro.com>
Discussed with: pjd (briefly)
Approved by: cperciva
MFC after: 1 week

Contrary to when returning in all-good cases at the end of functions we
did not free memory (1) or close the file descriptor (2) in error cases.

Reported by: Mark Johnston (1)
Reported by: attilio (2)
Reviewed by: jhb
Sponsored by: Sandvine Incorporated
MFC after: 1 week

Handle malloc() failures more gracefully by error'ing out rather than
segfaulting.

Submitted by: gcooper
MFC after: 1 week

- Save errno values before calling warn(3) so that errors are correctly
reported.
- Use powerof2() from <sys/param.h> rather than a copy and paste version.

Submitted by: gcooper
MFC after: 1 week

ntroduce mfiutil, a basic utility for managing LSI SAS-RAID & Dell PERC5/6
controllers. Controller, array, and drive status can be checked, basic
attributes can be changed, and arrays and spares can be created and deleted.
Controller firmware can also be flashed.

This does not replace MegaCLI, found in ports, as that is officially sanctioned
and supported by LSI and includes vastly more functionality. However, mfiutil
is open source and guaranteed to provide basic functionality, which can be
especially useful if you have a problem and can't get MegaCLI to work.

Approved by: re
Obtained from: Yahoo! Inc.