shells: do not frocibly enable test, echo and kill _applets_,

just build relevant source and use xxx_main functions.
build system: add a special case when we have exactly one applet enabled
(makes "true", "false", "basename" REALLY tiny).
getopt32: do not use stdio.

function                                             old     new   delta
getopt32                                            1385    1412     +27
make_device                                         1187    1200     +13
basename_main                                        120     127      +7
tcpudpsvd_main                                      1922    1926      +4
testcmd                                                5       -      -5
echocmd                                                5       -      -5
fuser_main                                          1243    1231     -12
------------------------------------------------------------------------------
(add/remove: 0/2 grow/shrink: 4/1 up/down: 51/-22)             Total: 29 bytes

1 files changed, 3 insertions, 22 deletions

diff --git a/shell/ash.c b/shell/ash.c
index 3651929c2..360d39b4c 100644
--- a/shell/ash.c
+++ b/shell/ash.c
@@ -8417,12 +8417,6 @@ returncmd(int argc ATTRIBUTE_UNUSED, char **argv)
 static int breakcmd(int, char **);
 static int dotcmd(int, char **);
 static int evalcmd(int, char **);
-#if ENABLE_ASH_BUILTIN_ECHO
-static int echocmd(int, char **);
-#endif
-#if ENABLE_ASH_BUILTIN_TEST
-static int testcmd(int, char **);
-#endif
 static int exitcmd(int, char **);
 static int exportcmd(int, char **);
 #if ENABLE_ASH_GETOPTS
@@ -8464,6 +8458,9 @@ static int ulimitcmd(int, char **);
  * Apart from the above, [[ expr ]] should work as [ expr ]
  */
 
+#define testcmd test_main
+#define echocmd echo_main
+
 /* Keep these in proper order since it is searched via bsearch() */
 static const struct builtincmd builtintab[] = {
         { BUILTIN_SPEC_REG      ".", dotcmd },
@@ -11506,22 +11503,6 @@ exitcmd(int argc ATTRIBUTE_UNUSED, char **argv)
         /* NOTREACHED */
 }
 
-#if ENABLE_ASH_BUILTIN_ECHO
-static int
-echocmd(int argc, char **argv)
-{
-        return echo_main(argc, argv);
-}
-#endif
-
-#if ENABLE_ASH_BUILTIN_TEST
-static int
-testcmd(int argc, char **argv)
-{
-        return test_main(argc, argv);
-}
-#endif
-
 /*
  * Read a file containing shell functions.
  */