spi: axi-spi-engine: fix version format string

The version format string in the AXI SPI Engine driver was probably
intended to print the version number in the same format as the DT
compatible string (e.g. 1.00.a). However, the version just uses
semantic versioning so formatting the patch number as a character
is not correct and would result in printing control characters for
patch numbers less than 32.

Fixes: b1353d1c

 ("spi: Add Analog Devices AXI SPI Engine controller support")
Signed-off-by: David Lechner <dlechner@baylibre.com>
Link: https://lore.kernel.org/r/20240412-axi-spi-engine-version-printf-v1-1-95e1e842c1a6@baylibre.com
Signed-off-by: Mark Brown <broonie@kernel.org>