hush: fix NOMMU hangs in pseudo_exec_argv. Add forgotted setting

 of signal mask. Reuse same help string in all shells.

function                                             old     new   delta
builtin_exit                                          49      47      -2
pseudo_exec_argv                                     149     145      -4
builtin_help                                          74      63     -11
------------------------------------------------------------------------------
(add/remove: 0/0 grow/shrink: 0/3 up/down: 0/-17)             Total: -17 bytes
   text    data     bss     dec     hex filename
 825379     476    7616  833471   cb7bf busybox_old
 825341     476    7616  833433   cb799 busybox_unstripped

1 files changed, 3 insertions, 1 deletions

diff --git a/shell/ash.c b/shell/ash.c
index 1cd205068..fe8c1bed2 100644
--- a/shell/ash.c
+++ b/shell/ash.c
@@ -12230,7 +12230,9 @@ helpcmd(int argc UNUSED_PARAM, char **argv UNUSED_PARAM)
         unsigned col;
         unsigned i;
 
-        out1fmt("\nBuilt-in commands:\n-------------------\n");
+        out1fmt("\n"
+                "Built-in commands:\n"
+                "------------------\n");
         for (col = 0, i = 0; i < ARRAY_SIZE(builtintab); i++) {
                 col += out1fmt("%c%s", ((col == 0) ? '\t' : ' '),
                                         builtintab[i].name + 1);