Merge tag 'imx-clk-4.4' into imx/dt

The i.MX clock updates for 4.4:
 - A couple of fixes on i.MX31 and i.MX35 clock initialization functions
   which makes mxc_timer_init() currently be called twice for DT boot.
 - Increase i.MX6UL AXI bus clock rate to 264MHz which is the optimal
   design target.
 - Add a few missing clocks, ADC clock for i.MX7D, OCOTP clock for
   Vybrid, and SPDIF_GCLK for i.MX6.
 - A series from Lucas to fix early debug UART clock setup.  This is
   currently a one-off fix for i.MX platform, and can be extended to
   become a generic solution later.