docs:spi: Add SPI Port mapping

Signed-off-by: Ajay Bhargav <[email protected]>

Author: ajaybhargav

docs/book/api/peri/spi.rst

@@ -1,6 +1,30 @@
 SPI
 ===
 
+.. |br| raw:: html
+
+	<br>
+
+SPI Port Mapping
+----------------
+
+GSM (MT2503, MT6261) and NB-IoT (MT2625) chipset supported modules expose only one
+I2C port. Following is the pin mapping for SPI Port 0.
+
++---------+------------------+-----------+-----------------+-----------+------------+------------+
+| SPI Pin |  MC20U Pin       |  M56 Pin  |  MC60 Pin       |  M66 Pin  |  BC20 Pin  |  SIM868    |
+|         |  |br| S20U Pin   |           |  |br| MC20 Pin  |           |            |  Pin       |
++=========+==================+===========+=================+===========+============+============+
+| MISO    |  Pin 61          |  Pin 15   |  Pin 61         |  Pin 31   |  Pin 61    |  Pin 41    |
++---------+------------------+-----------+-----------------+-----------+------------+------------+
+| MOSI    |  Pin 60          |  Pin 16   |  Pin 60         |  Pin 33   |  Pin 60    |  Pin 42    |
++---------+------------------+-----------+-----------------+-----------+------------+------------+
+| CLK     |  Pin 62          |  Pin 18   |  Pin 62         |  Pin 32   |  Pin 62    |  Pin 7     |
++---------+------------------+-----------+-----------------+-----------+------------+------------+
+| CS      |  Pin 59          |  Pin 4    |  Pin 59         |  Pin 30   |  Pin 59    |  Pin 5     |
++---------+------------------+-----------+-----------------+-----------+------------+------------+
+
+
 API Reference
 -------------