clk: qcom: Add support to initialize & handle dynamic update for alpha plls

Add support to do initial configuration for alpha plls and votable
alpha PLLs need to have the fsm mode enabled as part of the
initialization using flag 'SUPPORTS_FSM_MODE'.

Alpha PLLs can support two kinds of input signals, normal and latched.
The normal input is directly passed to the core, while the latched input
requires a latch and acknowledge sequence to be performed for the
changed input to propagate.

Alpha PLLs can support dynamic update with both kind of input signals.
The ones which support this using a latched interface however need to
follow the latch/wait-for-ack sequence to be performed when the rate
changes. Mark these with a new flag 'SUPPORTS_DYNAMIC_UPDATE' to handle
this as part of clk_alpha_pll_set_rate().

PLLs could require post div to be set at runtime, add a vco_data which
could be used for these settings.

Change-Id: Ia0b9a2a52a3b33b7b68409c19c460d717eb5c1e2
Signed-off-by: Amit Nischal <anischal@codeaurora.org>
Signed-off-by: Taniya Das <tdas@codeaurora.org>