ARM: shmobile: r8a7790: Correct typo in clocks

This is the r8a7790 SoC not the r8a77a4 SoC and
clocks are updated in r8a7790_clock_init not r8a73a4_clock_init.

Acked-by: Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
Signed-off-by: Simon Horman <horms+renesas@verge.net.au>