MLBEDSW-4692: Removed python invalid classifier from setup.py

Removed:
Programming Language :: Python :: 3.6 :: Only
As it is not a valid classifier

Signed-off-by: Patrik Gustavsson <patrik.gustavsson@arm.com>
Change-Id: Iebd1afa19952d7b90f4ddacf2ec5bf15252b9354
diff --git a/setup.py b/setup.py
index 29198a1..9133a12 100644
--- a/setup.py
+++ b/setup.py
@@ -77,13 +77,12 @@
         "Programming Language :: C",
         "Programming Language :: Python :: 3",
         "Programming Language :: Python :: 3.6",
-        "Programming Language :: Python :: 3.6 :: Only",
         "Topic :: Scientific/Engineering :: Artificial Intelligence",
         "Topic :: Software Development :: Compilers",
     ],
     keywords=["ethos-u", "vela compiler", "tflite", "npu"],
     packages=["ethosu.vela", "ethosu.vela.ethos_u55_regs", "ethosu.vela.tflite", "ethosu.mlw_codec"],
-    python_requires="~=3.6",  # We support only 3.6+
+    python_requires="~=3.6",
     install_requires=[
         "flatbuffers==1.12.0",
         "numpy>=1.16.6",