spi: amlogic: Fix error checking on regmap_write call

spi: amlogic: Fix error checking on regmap_write call

Currently a call to regmap_write is not being error checked because the
return checke is being performed on the variable ret and this variable
is not assigned the return value from the regmap_write call. Fix this
by adding in the missing assignment.

Fixes: 4670db6f32e9 ("spi: amlogic: add driver for Amlogic SPI Flash Controller")
Signed-off-by: Colin Ian King <colin.i.king@gmail.com>
Link: https://patch.msgid.link/20250913201612.1338217-1-colin.i.king@gmail.com
Signed-off-by: Mark Brown <broonie@kernel.org>