Simplify a few list() that only care about the first element

Simplify a few list() that only care about the first element

The nice thing about explode() is that the resulting array is
guaranteed to contain at least one element. The array can not be
empty.

In some of these cases it might be possible to use strstr() instead,
but that returns an empty string when the needle character is not
found. explode() returns the original string in this case.

Change-Id: I6ad1f3273defeaf36e2305fd871eaaf9d3c1e134