thermal: provide an UAPI header file

include/linux/thermal.h contains definitions for the Thermal generic
netlink family, but none of the valuable information relevant to
user-space such as the Genl family name, multicast group, version or
command set and data types is exported to user-space.

Export all the relevant generic netlink information to user-space to
make this genl family usable by user-space, and while at it, export
THERMAL_NAME_LENGTH since it limits name length for thermal_hwmon
devices.

Kbuild and MAINTAINERS are also updated accordingly to reflect this new
file: include/uapi/linux/thermal.h.

Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: Zhang Rui <rui.zhang@intel.com>

include/uapi/linux/thermal.h

@@ -0,0 +1,35 @@
+#ifndef _UAPI_LINUX_THERMAL_H
+#define _UAPI_LINUX_THERMAL_H
+
+#define THERMAL_NAME_LENGTH	20
+
+/* Adding event notification support elements */
+#define THERMAL_GENL_FAMILY_NAME                "thermal_event"
+#define THERMAL_GENL_VERSION                    0x01
+#define THERMAL_GENL_MCAST_GROUP_NAME           "thermal_mc_grp"
+
+/* Events supported by Thermal Netlink */
+enum events {
+	THERMAL_AUX0,
+	THERMAL_AUX1,
+	THERMAL_CRITICAL,
+	THERMAL_DEV_FAULT,
+};
+
+/* attributes of thermal_genl_family */
+enum {
+	THERMAL_GENL_ATTR_UNSPEC,
+	THERMAL_GENL_ATTR_EVENT,
+	__THERMAL_GENL_ATTR_MAX,
+};
+#define THERMAL_GENL_ATTR_MAX (__THERMAL_GENL_ATTR_MAX - 1)
+
+/* commands supported by the thermal_genl_family */
+enum {
+	THERMAL_GENL_CMD_UNSPEC,
+	THERMAL_GENL_CMD_EVENT,
+	__THERMAL_GENL_CMD_MAX,
+};
+#define THERMAL_GENL_CMD_MAX (__THERMAL_GENL_CMD_MAX - 1)
+
+#endif /* _UAPI_LINUX_THERMAL_H */