docs: add mt6795 to deprecated list

Change-Id: I2b3aa9bd0c23c360ecee673c68e1b2c92bc6d2be
diff --git a/docs/plat/deprecated.rst b/docs/plat/deprecated.rst
index 203ae00..7cc4258 100644
--- a/docs/plat/deprecated.rst
+++ b/docs/plat/deprecated.rst
@@ -16,3 +16,5 @@
 +================+================+====================+====================+
 |    sgm775      |      Arm       |        2.5         |       2.7          |
 +----------------+----------------+--------------------+--------------------+
+|    mt6795      |      MTK       |        2.5         |       2.7          |
++----------------+----------------+--------------------+--------------------+