[PATCH v3 4/9] versioncmp.c: refactor config reading next commit

["Ævar Arnfjörð Bjarmason" <avarab@gmail.com>]

Refactor the reading of the versionSort.suffix and
versionSort.prereleaseSuffix configuration variables to stay within
the bounds of our CodingGuidelines when it comes to line length, and
ta avoid repeating ourselves.

Let's also split out the names of the config variables into variables
of our own, so we don't have to repeat ourselves, and refactor the
nested if/else to avoid indenting it, and the existing bracing style
issue.

This all helps with the subsequent commit, where we'll need to start
checking different git_config_get_value_multi() return value. See
c026557a373 (versioncmp: generalize version sort suffix reordering,
2016-12-08) for the original implementation of most of this.

Moving the "initialized = 1" assignment allows us to move some of this
to the variable declarations in the subsequent commit.

Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
---
 versioncmp.c | 19 +++++++++++--------
 1 file changed, 11 insertions(+), 8 deletions(-)

diff --git a/versioncmp.c b/versioncmp.c
index 069ee94a4d7..323f5d35ea8 100644
--- a/versioncmp.c
+++ b/versioncmp.c
@@ -160,15 +160,18 @@ int versioncmp(const char *s1, const char *s2)
 	}
 
 	if (!initialized) {
-		const struct string_list *deprecated_prereleases;
+		const char *const newk = "versionsort.suffix";
+		const char *const oldk = "versionsort.prereleasesuffix";
+		const struct string_list *oldl;
+
+		prereleases = git_config_get_value_multi(newk);
+		oldl = git_config_get_value_multi(oldk);
+		if (prereleases && oldl)
+			warning("ignoring %s because %s is set", oldk, newk);
+		else if (!prereleases)
+			prereleases = oldl;
+
 		initialized = 1;
-		prereleases = git_config_get_value_multi("versionsort.suffix");
-		deprecated_prereleases = git_config_get_value_multi("versionsort.prereleasesuffix");
-		if (prereleases) {
-			if (deprecated_prereleases)
-				warning("ignoring versionsort.prereleasesuffix because versionsort.suffix is set");
-		} else
-			prereleases = deprecated_prereleases;
 	}
 	if (prereleases && swap_prereleases(s1, s2, (const char *) p1 - s1 - 1,
 					    &diff))
-- 
2.39.0.rc0.955.ge9b241be664