Fix the musb initialization sequence on AM335x.

According to http://e2e.ti.com/support/arm/sitara_arm/f/791/t/210729 the
USB reset pulse has an undocumented duration of 200ns and during this
period the module must not be acessed.

We wait for 100us to take into account for some imprecision of the early
DELAY() loop.

This fixes the eventual 'External Non-Linefetch Abort (S)' that happens at
boot while resetting the musb subsystem.

While here, enable the USB subsystem clock before the first access.

Discussed with: 	ian, adrian
MFC after:		2 weeks
DOF tables are aligned according to the DOF section's alignment constraint,
so take this into account when iterating over DOF tables.

PR:		195555
Submitted by:	Fedor Indutny <fedor@indutny.com> (original version)
MFC after:	1 week
mdoc fixes
mdoc fixes
mdoc fixes
mdoc fixes (escape the dot to prevent ... to be considered as a macro)
Escape Ed to prevent mandoc to avoid confusion with the mdoc's Ed macros
mdoc fix
mdoc: sort SEE ALSO.
Sort SEE ALSO
Escape Do to prevent mdoc(7) parser to get confused with the "Do" macro

Reported by:	sjg
sort SEE ALSO
sort SEE ALSO
Sort SEE ALSO
Merge remote-tracking branch 'freebsd/master' into hardened/current/master