ARM: OMAP2+: clock: add OMAP CCF convenience macros to mach-omap2/clock.h

Define four convenience macros to be used in the upcoming OMAP2+
common clock framework port.  Although the use of these macros will
make the data somewhat more difficult to read, they significantly reduce
the number of lines in the output patch data.

Most of these were created by Rajendra Nayak and Mike Turquette, as
far as I know.

Signed-off-by: Paul Walmsley <paul@pwsan.com>
[mturquette@ti.com: added DEFINE_CLK_OMAP_HSDIVIDER macro]
Signed-off-by: Mike Turquette <mturquette@ti.com>
Cc: Rajendra Nayak <rnayak@ti.com>
Signed-off-by: Paul Walmsley <paul@pwsan.com>