global: convert trivial usages of test <expr> -a/-o <expr>

Our coding guidelines say to not use `test` with `-a` and `-o` because
it can easily lead to bugs. Convert trivial cases where we still use
these to instead instead concatenate multiple invocations of `test` via
`&&` and `||`, respectively.

While not all of the converted instances can cause ambiguity, it is
worth getting rid of all of them regardless:

    - It becomes easier to reason about the code as we do not have to
      argue why one use of `-a`/`-o` is okay while another one isn't.

    - We don't encourage people to use these expressions.

Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

configure.ac

@@ -94,7 +94,7 @@ AC_DEFUN([GIT_PARSE_WITH_SET_MAKE_VAR],
 [AC_ARG_WITH([$1],
  [AS_HELP_STRING([--with-$1=VALUE], $3)],
  if test -n "$withval"; then
-  if test "$withval" = "yes" -o "$withval" = "no"; then
+  if test "$withval" = "yes" || test "$withval" = "no"; then
     AC_MSG_WARN([You likely do not want either 'yes' or 'no' as]
 		     [a value for $1 ($2).  Maybe you do...?])
   fi