setup: Fix paramiko version to 2.x.x and above

Unfortunately we can't fix this to version 2.1.x and above simply because it's
not available on currently shipping Debian distributions. Using 2.1.x would
allow us to set environment variables, however.

Change-Id: I9428f87d80fd6c5b504e6e62ffa2c4f4593a4a8d
diff --git a/setup.py b/setup.py
index c716bb7..f3a42d2 100755
--- a/setup.py
+++ b/setup.py
@@ -31,7 +31,7 @@
     python_requires='>=3.5.0',
     install_requires=[
         'zeroconf',
-        'paramiko'
+        'paramiko>=2.0.0'
     ],
     data_files=[('share/man/man1', ['man/mdt.1'])],
     package_data={