configure: default to --with-webdav=curl

Change-Id: I00842dec9512a8fe0d68a507e8a1467df97709f2
Reviewed-on: https://gerrit.libreoffice.org/c/core/+/123461
Tested-by: Jenkins
Reviewed-by: Michael Stahl <michael.stahl@allotropia.de>
diff --git a/configure.ac b/configure.ac
index 71cb030..593170c 100644
--- a/configure.ac
+++ b/configure.ac
@@ -10852,10 +10852,7 @@ AC_SUBST(ENABLE_RANDR)

if test "$test_webdav" = yes; then
    if test -z "$with_webdav"; then
        WITH_WEBDAV=neon
        if test "$enable_mpl_subset" = yes; then
            WITH_WEBDAV=serf
        fi
        WITH_WEBDAV=curl
    else
        WITH_WEBDAV="$with_webdav"
    fi