[ARM] integrator: convert to clkdev and lookup clocks by device name

People often point to the Integrator/Versatile/Realview
implementations to justify using the consumer name as the sole
selector for clocks.

Eliminate this excuse by changing the Integrator implementation, so
it provides a better example of how it should be done.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig
index d4fcf30..f1ac393 100644
--- a/arch/arm/Kconfig
+++ b/arch/arm/Kconfig
@@ -210,6 +210,7 @@
 	bool "ARM Ltd. Integrator family"
 	select ARM_AMBA
 	select HAVE_CLK
+	select COMMON_CLKDEV
 	select ICST525
 	help
 	  Support for ARM's Integrator platform.