Corrected spelling mistake on README file.

README.rst

@@ -46,7 +46,7 @@ Please use the GitHub system to report feature request and bugs.
 Known issues
 ------------
 
-CMTS and CM MIC are have the wrong value when calculated on a big endian CPU. Using the MIC values and a big endian CPU should be avoided in production systems.
+CMTS and CM MIC have the wrong value when calculated on a big endian CPU. Using the MIC values and a big endian CPU should be avoided in production systems.
 
 Quoting the hex strings will result in a crash. Do not use something similar to "0xABCD".