- Copy stable/10@296371 to releng/10.3 in preparation for 10.3-RC1
builds.
- Update newvers.sh to reflect RC1.
- Update __FreeBSD_version to reflect 10.3.
- Update default pkg(8) configuration to use the quarterly branch.

Approved by: re (implicit)

MFC 264977:

Stop calling imx51_ccm_foo() clock functions from imx6 code. Instead
define a few imx_ccm_foo() functions that are implemented by the imx51
or imx6 ccm code.

MFC r261410

Follow r261352 by updating all drivers which are children of simplebus
to check the status property in their probe routines.

MFC r257383, r257384:

Add some bare-bones support for enabling usb and usbphy clocks.

Add a "no-op" USB PHY driver for imx-family SoCs.

Add a "no-op" USB PHY driver for imx-family SoCs. This is used when the
phy clocks need to be enabled, but no other hardware setup is needed to
make the phy work.