ARM: shmobile: r8a7740: add MSTP clock assignments to DT

Assigns clocks to ether, i2c*, scif*, tpu, mmcif0, sdhi*, and fsi2.

Signed-off-by: Ulrich Hecht <ulrich.hecht+renesas@gmail.com>
Acked-by: Magnus Damm <damm+renesas@opensource.se>
Signed-off-by: Simon Horman <horms+renesas@verge.net.au>