.gitignore: add *.pyc and *.pyo

.gitignore needs to contain these two items, otherwise, we get unstaged
change about meta-oe/lib/oeqa/selftest/cases/__pycache__/ every time
we run oe-selftest.

Signed-off-by: Chen Qi <Qi.Chen@windriver.com>
Signed-off-by: Khem Raj <raj.khem@gmail.com>

.gitignore

@@ -1,3 +1,5 @@
+*.pyc
+*.pyo
 /*.patch
 *.swp
 *.orig