string_list API users: use string_list_init_{no,}dup
Follow-up on the introduction of string_list_init_nodup() and string_list_init_dup() in the series merged in bd4232fac33 (Merge branch 'ab/struct-init', 2021-07-16) and convert code that implicitly relied on xcalloc() being equivalent to the initializer to use xmalloc() and string_list_init_{no,}dup() instead. In the case of get_unmerged() in merge-recursive.c we used the combination of xcalloc() and assigning "1" to "strdup_strings" to get what we'd get via string_list_init_dup(), let's use that instead. Adjacent code in cmd_format_patch() will be changed in a subsequent commit, since we're changing that let's change the other in-tree patterns that do the same. Let's also convert a "x == NULL" to "!x" per our CodingGuidelines, as we need to change the "if" line anyway. Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>