soc: bcm: bcm2835-pm: Fix error paths of initialization.
The clock driver may probe after ours and so we need to pass the
-EPROBE_DEFER out. Fix the other error path while we're here.
v2: Use dom->name instead of dom->gov as the flag for initialized
domains, since we aren't setting up a governor. Make sure to
clear ->clk when no clk is present in the DT.
Signed-off-by: Eric Anholt <eric@anholt.net> Fixes: 670c672608a1 ("soc: bcm: bcm2835-pm: Add support for power domains under a new binding.")