clk: x86: Set default parent to 48Mhz

System clk provided in ST soc can be set to:
48Mhz, non-spread
25Mhz, spread
To get accurate rate, we need it to set it at non-spread
option which is 48Mhz.

Signed-off-by: Akshu Agrawal <akshu.agrawal@amd.com>
Reviewed-by: Daniel Kurtz <djkurtz@chromium.org>
Fixes: 421bf6a1 ("clk: x86: Add ST oscout platform clock")
Signed-off-by: Stephen Boyd <sboyd@kernel.org>