dm: i2c: use CONFIG_IS_ENABLED macro for DM_I2C/DM_I2C_GPIO

Use CONFIG_IS_ENABLED() macro, which provides more convenient
way to check $(SPL)DM_I2C/$(SPL)DM_I2C_GPIO configs
for both SPL and U-Boot proper.

CONFIG_IS_ENABLED(DM_I2C) expands to:
- 1 if CONFIG_SPL_BUILD is undefined and CONFIG_DM_I2C is set to 'y',
- 1 if CONFIG_SPL_BUILD is defined and CONFIG_SPL_DM_I2C is set to 'y',
- 0 otherwise.

All occurences were replaced automatically using these bash cmds:
$ find . -type f -exec sed -i
     's/ifndef CONFIG_DM_I2C/if !CONFIG_IS_ENABLED(DM_I2C)/g' {} +
$ find . -type f -exec sed -i
    's/ifdef CONFIG_DM_I2C/if CONFIG_IS_ENABLED(DM_I2C)/g' {} +
$ find . -type f -exec sed -i
    's/defined(CONFIG_DM_I2C)/CONFIG_IS_ENABLED(DM_I2C)/g' {} +
$ find . -type f -exec sed -i
    's/ifndef CONFIG_DM_I2C_GPIO/if !CONFIG_IS_ENABLED(DM_I2C_GPIO)/g' {} +
$ find . -type f -exec sed -i
    's/ifdef CONFIG_DM_I2C_GPIO/if CONFIG_IS_ENABLED(DM_I2C_GPIO)/g' {} +
$ find . -type f -exec sed -i
    's/defined(CONFIG_DM_I2C_GPIO)/CONFIG_IS_ENABLED(DM_I2C_GPIO)/g' {} +

Reviewed-by: Heiko Schocher <hs@denx.de>
Reviewed-by: Simon Glass <sjg@chromium.org>
Signed-off-by: Igor Opaniuk <igor.opaniuk@foundries.io>
Reviewed-by: Tom Rini <trini@konsulko.com>
Reviewed-by: Priyanka Jain <priyanka.jain@nxp.com>
diff --git a/board/freescale/ls1046afrwy/ls1046afrwy.c b/board/freescale/ls1046afrwy/ls1046afrwy.c
index 9813a36..f1709dc 100644
--- a/board/freescale/ls1046afrwy/ls1046afrwy.c
+++ b/board/freescale/ls1046afrwy/ls1046afrwy.c
@@ -42,7 +42,7 @@
 {
 	int ret;
 
-#ifdef CONFIG_DM_I2C
+#if CONFIG_IS_ENABLED(DM_I2C)
 	struct udevice *dev;
 
 	ret = i2c_get_chip_for_busnum(bus_num, I2C_MUX_PCA_ADDR_PRI,