iio:adc:qcom-spmi-vadc silence a long constant warning.

It is meant to be long and is only added to an s64.
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
Cc: Rama Krishna Phani A <rphani@codeaurora.org>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>

drivers/iio/adc/qcom-spmi-vadc.c

@@ -101,7 +101,7 @@
 #define KELVINMIL_CELSIUSMIL			273150
 
 #define PMI_CHG_SCALE_1				-138890
-#define PMI_CHG_SCALE_2				391750000000
+#define PMI_CHG_SCALE_2				391750000000LL
 
 #define VADC_CHAN_MIN			VADC_USBIN
 #define VADC_CHAN_MAX			VADC_LR_MUX3_BUF_PU1_PU2_XO_THERM