OMAP: clockdomain: Arch specific funcs for sleep/wakeup of clkdm

Define the following architecture specific funtions for omap2/3/4
.clkdm_sleep
.clkdm_wakeup

Convert the platform-independent framework to call these functions.
Also rename the api's by removing the omap2_ preamble.
Hence call omap2_clkdm_wakeup as clkdm_wakeup and
omap2_clkdm_sleep as clkdm_sleep.

Signed-off-by: Rajendra Nayak <rnayak@ti.com>
[paul@pwsan.com: fixed omap3_clkdm_clear_all_sleepdeps() and
 omap2_clkdm_clear_all_wkdeps() to test against the correct
 loop termination condition; thanks to Kevin Hilman for finding and
 helping fix]
Cc: Kevin Hilman <khilman@ti.com>
Signed-off-by: Paul Walmsley <paul@pwsan.com>