clk: msm: clock-osm: Request Nominal Fmax frequency after OSM enable

Index 0 LUT entry must be selected before enabling OSM. The final
desired boot rate should be selected once OSM is enabled.
Fix this.

CRs-Fixed: 1082804
Change-Id: I7901df15ec03273304c5e4d417f272497ad1523c
Signed-off-by: Osvaldo Banuelos <osvaldob@codeaurora.org>