OMAP: process tput request made before PM init.

Because driver load order is uncertain, drivers could request bus
throughput constraints before the PM subsystem had initialized.  The
constraints would be recorded, but would have no effect on the actual
L3 clock.  This change suppresses attempts to set L3 scaling before PM
has initialized, and causes the PM subsystem to apply any pending bus
throughput constraints immediately after it has initialized itself.

Change-Id: If2a1f5315b8c1b084e4e4b3ce8e6844d92dd59b6
Signed-off-by: John Grossman <johngro@google.com>
Signed-off-by: Ruslan Bilovol <ruslan.bilovol@ti.com>