ALSA: hda: cs35l41: fix building without CONFIG_SPI

When CONFIG_SPI is disabled, the driver produces unused-variable warning:

sound/pci/hda/cs35l41_hda_property.c: In function 'generic_dsd_config':
sound/pci/hda/cs35l41_hda_property.c:181:28: error: unused variable 'spi' [-Werror=unused-variable]
  181 |         struct spi_device *spi;
      |                            ^~~
sound/pci/hda/cs35l41_hda_property.c:180:27: error: unused variable 'cs_gpiod' [-Werror=unused-variable]
  180 |         struct gpio_desc *cs_gpiod;
      |                           ^~~~~~~~

Avoid these by turning the preprocessor contionals into equivalent C code,
which also helps readability.

Fixes: 916d051 ("ALSA: hda: cs35l41: Only add SPI CS GPIO if SPI is enabled in kernel")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Link: https://lore.kernel.org/r/20240103102606.3742476-1-arnd@kernel.org
Signed-off-by: Takashi Iwai <tiwai@suse.de>

Author: arndb

sound/pci/hda/cs35l41_hda_property.c

@@ -211,7 +211,6 @@ static int generic_dsd_config(struct cs35l41_hda *cs35l41, struct device *physde
 	if (cfg->bus == SPI) {
 		cs35l41->index = id;
 
-#if IS_ENABLED(CONFIG_SPI)
 		/*
 		 * Manually set the Chip Select for the second amp <cs_gpio_index> in the node.
 		 * This is only supported for systems with 2 amps, since we cannot expand the
@@ -220,7 +219,7 @@ static int generic_dsd_config(struct cs35l41_hda *cs35l41, struct device *physde
 		 * uses a native chip select), to ensure the second amp does not clash with the
 		 * first.
 		 */
-		if (cfg->cs_gpio_index >= 0) {
+		if (IS_ENABLED(CONFIG_SPI) && cfg->cs_gpio_index >= 0) {
 			spi = to_spi_device(cs35l41->dev);
 
 			if (cfg->num_amps != 2) {
@@ -251,7 +250,6 @@ static int generic_dsd_config(struct cs35l41_hda *cs35l41, struct device *physde
 				spi_setup(spi);
 			}
 		}
-#endif
 	} else {
 		if (cfg->num_amps > 2)
 			/*