OMAP2xxx clock: move osc_clk code into mach-omap2/clkt2xxx_osc.c

Move the osc_clk clock functions from clock2xxx.c to
mach-omap2/clkt2xxx_osc.  This is intended to make the clock code
easier to understand, since all of the functions needed to manage the
osc_clk are now located in their own file, rather than being mixed
with other, unrelated functions.

Clock debugging is also now more finely-grained, since the DEBUG
macro can now be defined for osc_clk clocks alone.  This
should reduce unnecessary console noise when debugging.

Also, if at some future point the mach-omap2/ directory is split
into OMAP2/3/4 variants, this clkt file can be placed in the mach-omap2xxx/
directory, rather than shared with other chip types that don't use this
clock type.

Thanks to Alexander Shishkin <virtuoso@slind.org> for his comments to
improve the patch description.

Signed-off-by: Paul Walmsley <paul@pwsan.com>
Cc: Alexander Shishkin <virtuoso@slind.org>
diff --git a/arch/arm/mach-omap2/clock2xxx.h b/arch/arm/mach-omap2/clock2xxx.h
index 3f1672e..3b0610d 100644
--- a/arch/arm/mach-omap2/clock2xxx.h
+++ b/arch/arm/mach-omap2/clock2xxx.h
@@ -18,6 +18,7 @@
 int omap2_reprogram_dpllcore(struct clk *clk, unsigned long rate);
 unsigned long omap2xxx_clk_get_core_rate(struct clk *clk);
 u32 omap2xxx_get_apll_clkin(void);
+u32 omap2xxx_get_sysclkdiv(void);
 
 /* REVISIT: These should be set dynamically for CONFIG_MULTI_OMAP2 */
 #ifdef CONFIG_ARCH_OMAP2420