[media] rc: rename the remaining things to rc_core

The Remote Controller subsystem is meant to be used not only by Infra Red
but also for similar types of Remote Controllers. The core is not specific
to Infra Red. As such, rename:
	- ir-core.h to rc-core.h
	- IR_CORE to RC_CORE
	- namespace inside rc-core.c/rc-core.h

To be consistent with the other changes.

No functional change on this patch.

Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
diff --git a/drivers/media/dvb/dvb-usb/Kconfig b/drivers/media/dvb/dvb-usb/Kconfig
index 2525d3b..3d48ba0 100644
--- a/drivers/media/dvb/dvb-usb/Kconfig
+++ b/drivers/media/dvb/dvb-usb/Kconfig
@@ -1,6 +1,6 @@
 config DVB_USB
 	tristate "Support for various USB DVB devices"
-	depends on DVB_CORE && USB && I2C && IR_CORE
+	depends on DVB_CORE && USB && I2C && RC_CORE
 	help
 	  By enabling this you will be able to choose the various supported
 	  USB1.1 and USB2.0 DVB devices.