i7300_idle: remove unused file

i7300_idle.h is not being called by any source file and contains calls to
pci_get_bus_and_slot() that we are trying to deprecate. Remove unused file.

Signed-off-by: Sinan Kaya <okaya@codeaurora.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>