ARM: DRA7: Add support for soc_is_dra74x() and soc_is_dra72x() variants

commit af438fec upstream.

Use the corresponding compatibles to identify the devices.

Signed-off-by: Rajendra Nayak <rnayak@ti.com>
Signed-off-by: Lokesh Vutla <lokeshvutla@ti.com>
Acked-by: Nishanth Menon <nm@ti.com>
Tested-by: Nishanth Menon <nm@ti.com>
Signed-off-by: Paul Walmsley <paul@pwsan.com>
Cc: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>