soc/intel/quark: Add pwrs in <soc/nvs.h>

For the time being every soc/intel selects ACPI_SOC_NVS
and pwrs is a required field for the common initialisation
implementation of followup work.

Change-Id: I4a0c7eb35f0646898e49fad15c6448607c398731
Signed-off-by: Kyösti Mälkki <kyosti.malkki@gmail.com>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/49493
Reviewed-by: Angel Pons <th3fanbus@gmail.com>
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>

src/soc/intel/quark/include/soc/nvs.h

@@ -7,6 +7,7 @@
 
 struct __packed global_nvs {
 	uint32_t	cbmc; /* 0x00 - 0x03 - coreboot Memory Console */
+	uint8_t		pwrs; /* 0x4 - Power state (AC = 1) */
 };
 
 #endif /* SOC_INTEL_QUARK_NVS_H */