clk: pxa910: Move number of clocks to driver source

The number of clocks should not be in the dt binding as it is not used
by the respective device tree and thus needlessly bloats the ABI.

Move this number of clocks into the driver source.

Signed-off-by: Duje Mihanović <duje.mihanovic@skole.hr>
Link: https://lore.kernel.org/r/20230812-mmp-nr-clks-v2-4-f9271bd7eaa5@skole.hr


Acked-by: Conor Dooley <conor.dooley@microchip.com>
Signed-off-by: Stephen Boyd <sboyd@kernel.org>