test-lint: echo -e (or -E) is not portable

Some implementations of `echo` support the '-e' option to enable
backslash interpretation of the following string.
As an addition, they support '-E' to turn it off.

However, none of these are portable, POSIX doesn't even mention them,
and many implementations don't support them.

A check for '-n' is already done in check-non-portable-shell.pl,
extend it to cover '-n', '-e' or '-E'.

Signed-off-by: Torsten Bögershausen <[email protected]>
Signed-off-by: Junio C Hamano <[email protected]>

Author: tboegi

t/check-non-portable-shell.pl

@@ -17,7 +17,7 @@ sub err {
 while (<>) {
 	chomp;
 	/\bsed\s+-i/ and err 'sed -i is not portable';
-	/\becho\s+-n/ and err 'echo -n is not portable (please use printf)';
+	/\becho\s+-[neE]/ and err 'echo with option is not portable (please use printf)';
 	/^\s*declare\s+/ and err 'arrays/declare not portable';
 	/^\s*[^#]\s*which\s/ and err 'which is not portable (please use type)';
 	/\btest\s+[^=]*==/ and err '"test a == b" is not portable (please use =)';