docs: hwmon: Add an index file and rename docs to *.rst

Now that all files were converted to ReST format, rename them
and add an index.

Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>

Documentation/hwmon/tmp103.rst

@@ -0,0 +1,33 @@
+Kernel driver tmp103
+====================
+
+Supported chips:
+
+  * Texas Instruments TMP103
+
+    Prefix: 'tmp103'
+
+    Addresses scanned: none
+
+    Product info and datasheet: http://www.ti.com/product/tmp103
+
+Author:
+
+	Heiko Schocher <hs@denx.de>
+
+Description
+-----------
+
+The TMP103 is a digital output temperature sensor in a four-ball
+wafer chip-scale package (WCSP). The TMP103 is capable of reading
+temperatures to a resolution of 1°C. The TMP103 is specified for
+operation over a temperature range of –40°C to +125°C.
+
+Resolution: 8 Bits
+Accuracy: ±1°C Typ (–10°C to +100°C)
+
+The driver provides the common sysfs-interface for temperatures (see
+Documentation/hwmon/sysfs-interface.rst under Temperatures).
+
+Please refer how to instantiate this driver:
+Documentation/i2c/instantiating-devices