xtensa: don't use echo -e needlessly

commit 123f15e669d5a5a2e2f260ba4a5fc2efd93df20e upstream.

-e is not needed to output strings without escape sequences. This breaks
big endian FSF build when the shell is dash, because its builtin echo
doesn't understand '-e' switch and outputs it in the echoed string.

Reported-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
Signed-off-by: Chris Zankel <chris@zankel.net>
Cc: Sudip Mukherjee <sudipm.mukherjee@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>