spi: cadence-qspi: Fix style and improve readability

spi: cadence-qspi: Fix style and improve readability

It took me several seconds to correctly understand this block. I
understand the goal: showing that we are in the if, or in one of the two
other cases. Improve the organization of the code to both improve
readability and fix the style.

Suggested-by: Pratyush Yadav <pratyush@kernel.org>
Tested-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Signed-off-by: Miquel Raynal (Schneider Electric) <miquel.raynal@bootlin.com>
Tested-by: Santhosh Kumar K <s-k6@ti.com>
Link: https://patch.msgid.link/20260122-schneider-6-19-rc1-qspi-v4-4-f9c21419a3e6@bootlin.com
Signed-off-by: Mark Brown <broonie@kernel.org>