[busybox] Store history after every line. Fixes JB#53061

When busybox is killed using SIGHUP it doesn't save out the history
file. This change configures busybox to save the history out after each
line, rather than on exit, so that exiting with SIGHUP (as Fingerterm
does) won't cause the history to be lost.

rpm/busybox-sailfish.config

@@ -101,7 +101,7 @@ CONFIG_FEATURE_EDITING_MAX_LEN=1024
 # CONFIG_FEATURE_EDITING_VI is not set
 CONFIG_FEATURE_EDITING_HISTORY=255
 CONFIG_FEATURE_EDITING_SAVEHISTORY=y
-CONFIG_FEATURE_EDITING_SAVE_ON_EXIT=y
+CONFIG_FEATURE_EDITING_SAVE_ON_EXIT=n
 CONFIG_FEATURE_REVERSE_SEARCH=y
 CONFIG_FEATURE_TAB_COMPLETION=y
 CONFIG_FEATURE_USERNAME_COMPLETION=y