[COMMON] Get rid of "x-hack" in shell scripts

[COMMON] Get rid of "x-hack" in shell scripts

$ find . -name *.sh -print |xargs grep -l '"x'| xargs sed -i 's/"x/"/g'

The "x-hack" is a historical workaround for some old UNIX shells with
buggy condition comparison code. None of them is still used today.
Recent POSIX specifications now guarantee it should work without it
in any modern POSIX shell.

More details at
https://www.vidarholen.net/contents/blog/?p=1035
https://github.com/koalaman/shellcheck/wiki/SC2268

Issue-ID: OOM-2643
Signed-off-by: Guillaume Lambert <guillaume.lambert@orange.com>
Change-Id: Ic01bbc5faee9492dba5b5d4dea0f659540da2c24