Setting LC_ALL=C breaks python apps doing I/O on UTF-8 source
files. In particular this broke glib-mkenums

    Traceback (most recent call last):
  File "/usr/bin/glib-mkenums", line 669, in <module>
    process_file(fname)
  File "/usr/bin/glib-mkenums", line 406, in process_file
    line = curfile.readline()
  File "/usr/lib64/python3.6/encodings/ascii.py", line 26, in decode
    return codecs.ascii_decode(input, self.errors)[0]
UnicodeDecodeError: 'ascii' codec can't decode byte 0xc3 in position 115: ordinal not in range(128)

Signed-off-by: Daniel P. Berrange <berrange@redhat.com>