VAL = "" (not shown)
VAL = " " (shown as "")
VAL = " x" (shown as "x")
would all show up rather differently to what would be expected in the
bitbake -e output. This fixes things so they appear consistently.
The output for running some shell functions may also change slightly
but shouldn't change in a way that is likely to cause problems.
[YOCTO #5507]
(Bitbake rev: fcba5ef0053dc0ef5360e4912609e5d52f5046b0)
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>