ash: fix another bug detected by var_bash4.tests

... but var_bash4.tests still does not pass!

function                                             old     new   delta
expandarg                                            959     962      +3
localcmd                                             259     257      -2
readtoken1                                          3275    3260     -15
subevalvar                                          1178    1141     -37
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(add/remove: 0/0 grow/shrink: 1/3 up/down: 3/-54)             Total: -51 bytes

Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
1 file changed