arm64: dts: meson-sm1: fix typo in opp table

The freqency 1512000000 should be 1500000000.

Signed-off-by: Dongjin Kim <tobetter@gmail.com>
Fixes: 3d9e7648

 ("arm64: dts: meson-sm1-sei610: enable DVFS")
Reviewed-by: Neil Armstrong <narmstrong@baylibre.com>
Signed-off-by: Kevin Hilman <khilman@baylibre.com>
Link: https://lore.kernel.org/r/20201130060320.GA30098@anyang-linuxfactory-or-kr