OMAP3: PM: idle: Remove fclk check for idle loop

This patch removes the check to see if some functional clocks are
still enabled before entering sleep.  This is no longer needed when
using safe state (C1) that keeps CORE active.

Signed-off-by: Peter 'p2' De Schrijver <peter.de-schrijver@nokia.com>
Signed-off-by: Kevin Hilman <khilman@deeprootsystems.com>