OMAP4: DPLL csacading: CPUfreq: manage DPLL cascading constraint

Only release a DPLL cascading constraint when at the lowest OPP,
otherwise hold a constraint blocking DPLL cascading entry.
targa: remove ramdisk mod from build script
OMAP2PLUS:fix for TF doesn't work when CPU1 on/off

TI thermal framework: rework initialization sequence

The initialization of max_thermal was placed in function
which is executed for each CPU1 start. The old value of
max_thermal is lost in this case and is set to max_freq.
As result, the omap_thermal_step_freq_down() can't
reduce the frequency if CPU1 is  switched on/off often.
OMAP2PLUS: TF: rework initialization sequence

The duty cooling device is being registered in the
wrong place. We don't want to register a cooling device
every time a CPU is initialized.  Thus, this patch moves
the cooling device registration to module init instead.