masterimage.py: rename parameter "params" in start() to "extra_bootparams"

This matches how it is called, and how it is named in qmeu target.

[YOCTO #11524]

(From OE-Core rev: 64614ab6894143fa4876558cbe3d2954e5b08eac)

Signed-off-by: Erik Botö <erik.boto@pelagicore.com>
Signed-off-by: Stephano Cetola <stephano.cetola@linux.intel.com>
Signed-off-by: Ross Burton <ross.burton@intel.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>

meta/lib/oeqa/controllers/masterimage.py

@@ -143,7 +143,7 @@ class MasterImageHardwareTarget(oeqa.targetcontrol.BaseTarget, metaclass=ABCMeta
     def _deploy(self):
         pass
 
-    def start(self, params=None):
+    def start(self, extra_bootparams=None):
         bb.plain("%s - boot test image on target" % self.pn)
         self._start()
         # set the ssh object for the target/test image