OMAP2/3/4 clock: omap2_clk_prepare_for_reboot() is OMAP2xxx-only

omap2_clk_prepare_for_reboot() is only applicable to OMAP2xxx chips,
so rename it to omap2xxx_clk_prepare_for_reboot() and only call it when
running on OMAP2xxx chips.  Remove the old stub in the OMAP3 clock code.

Signed-off-by: Paul Walmsley <paul@pwsan.com>
6 files changed