drivers/fdc2x1x: Require full C library, not just newlib

This driver uses the math library, so it cannot use the minimal C
library. However, it should be fine with any complete C library, not just
newlib.

Signed-off-by: Keith Packard <keithp@keithp.com>

drivers/sensor/fdc2x1x/Kconfig

@@ -7,7 +7,7 @@ menuconfig FDC2X1X
 	bool "FDC2X1X Capacitance-to-Digital Converter"
 	default y
 	depends on DT_HAS_TI_FDC2X1X_ENABLED
-	depends on NEWLIB_LIBC || EXTERNAL_LIBC
+	depends on REQUIRES_FULL_LIBC || EXTERNAL_LIBC
 	select I2C
 	help
 	  Enable driver for FDC2X1X Capacitance-to-Digital Converter.