Fix a bunch of stack leaks. These were theoretically harmless, except that

they would leave enough elements on the stack that if you escaped to the
loader prompt and then typed 'setenv', it would pull in all of the leaked
junk and cause an exception in the environment.  There still seems to be
3 leaked elements, but they don't appear to be coming from this file.

sys/boot/forth/beastie.4th

@@ -69,7 +69,7 @@ variable rebootkey
 2dup at-xy ."                \       /       /\" 1+
 2dup at-xy ."           ______( (_  / \______/" 1+
 2dup at-xy ."         ,'  ,-----'   |" 1+
-at-xy ."         `--{__________) " 1+
+at-xy ."         `--{__________) "
 ;
 
 : boring-beastie ( x y -- )
@@ -121,6 +121,8 @@ at-xy ."         `--{__________) " 1+
 		s" 0" compare 0<> if
 			false exit
 		then
+	else
+		drop
 	then
 	true
 ;
@@ -147,6 +149,7 @@ at-xy ."         `--{__________) " 1+
 	13 6 at-xy ." Welcome to FreeBSD!"
 	printmenuitem ."  Boot FreeBSD [default]" bootkey !
 	s" arch-i386" environment? if
+		drop
 		printmenuitem ."  Boot FreeBSD with ACPI " bootacpikey !
 		acpienabled? if
 			." disabled"
@@ -161,9 +164,10 @@ at-xy ."         `--{__________) " 1+
 	printmenuitem ."  Boot FreeBSD with verbose logging" bootverbosekey !
 	printmenuitem ."  Escape to loader prompt" escapekey !
 	s" arch-i386" environment? if
+		drop
 		printmenuitem ."  Boot FreeBSD with USB keyboard" bootusbkey !
 	else
-		-2 bootacpikey !
+		-2 bootusbkey !
 	then
 	printmenuitem ."  Reboot" rebootkey !
 	menuX @ 20 at-xy
@@ -174,7 +178,6 @@ at-xy ."         `--{__________) " 1+
 ;
 
 : tkey
-	dup
 	seconds +
 	begin 1 while
 		over 0<> if
@@ -202,6 +205,8 @@ set-current
 		s" YES" compare-insensitive 0= if
 			exit
 		then
+	else
+		drop
 	then
 	beastie-menu
 	s" autoboot_delay" getenv
@@ -211,7 +216,7 @@ set-current
 	else
 		0 0 2swap >number drop drop drop
 	then
-	begin true while
+	begin
 		dup tkey
 		0 25 at-xy
 		dup 32 = if nip 0 swap then
@@ -235,6 +240,7 @@ set-current
 		then
 		dup bootsafekey @ = if
 			s" arch-i386" environment? if
+				drop
 				s" acpi_load" unsetenv
 				s" 1" s" hint.acpi.0.disabled" setenv
 				s" 1" s" loader.acpi_disabled_by_user" setenv
@@ -260,7 +266,7 @@ set-current
 			exit
 		then
 		rebootkey @ = if 0 reboot then
-	repeat
+	again
 ;
 
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