add HAVE_CLK to Kconfig, for driver dependencies

Flag platforms as HAVE_CLK (or not) in Kconfig, based on whether they
support <linux/clk.h> calls, so that otherwise portable drivers which need
those calls can list that dependency.

Something like this is a prerequisite for merging the musb_hdrc driver,
currently used on platforms including Davinci, OMAP2430, OMAP3xx ...  and
the discrete TUSB6010 chip, which doesn't have a natural platform
dependency.  (Used with OMAP 2420 in current Nokia N8x0 tablets.)

Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Cc: Russell King <rmk@arm.linux.org.uk>
Acked-by: Haavard Skinnemoen <hskinnemoen@atmel.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Paul Mundt <lethal@linux-sh.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/arch/avr32/Kconfig b/arch/avr32/Kconfig
index 45d63c9..df4adef 100644
--- a/arch/avr32/Kconfig
+++ b/arch/avr32/Kconfig
@@ -10,6 +10,7 @@
 	# With EMBEDDED=n, we get lots of stuff automatically selected
 	# that we usually don't need on AVR32.
 	select EMBEDDED
+	select HAVE_CLK
 	select HAVE_OPROFILE
 	select HAVE_KPROBES
 	help