ARM: OMAP4: clock: Convert to common clk

ARM: OMAP4: clock: Convert to common clk

Convert all OMAP4 specific platform files to use COMMON clk
and keep all the changes under the CONFIG_COMMON_CLK macro check
so it does not break any existing code. At a later point switch
to COMMON clk and get rid of all old/legacy code.

This converts all apis which will be called directly from COMMON
clk to take a struct clk_hw parameter, and all the internal platform
apis to take a struct clk_hw_omap parameter.

Changes are based off the original patch from Mike Turquette.

Signed-off-by: Rajendra Nayak <rnayak@ti.com>
[paul@pwsan.com: created new omap2_clksel_find_parent_index() rather than
 modifying omap2_init_clksel_parent(); moved clkhwops_iclk_wait to
 clkt_iclk.c to fix OMAP4-only builds; added clk-provider.h include to clock.h
 to try to fix some 3430-builds]
[mturquette@ti.com: squash patch for omap2_clkops_{en,dis}able_clkdm;
 omap2_dflt_clk_is_enabled should not enable clocks]
Signed-off-by: Mike Turquette <mturquette@ti.com>
[paul@pwsan.com: fix compiler warning; update to apply; added kerneldoc on
 non-trivial new functions; added the dpll3xxx clockdomain modifications]
Signed-off-by: Paul Walmsley <paul@pwsan.com>