CLK: TI: clk-54xx: Set the rate for dpll_abe_m2x2_ck

In order to get correct clock dividers for AESS/ABE we need to set the
dpll_abe_m2x2_ck rate to be double of dpll_abe_ck.

Signed-off-by: Peter Ujfalusi <peter.ujfalusi@ti.com>
Signed-off-by: Tero Kristo <t-kristo@ti.com>