fileio: in envfiles, do not skip lines following empty lines

https://bugs.freedesktop.org/show_bug.cgi?id=63477

src/shared/conf-parser.c

@@ -174,7 +174,7 @@ static int parse_line(
         if (!*l)
                 return 0;
 
-        if (strchr(COMMENTS, *l))
+        if (strchr(COMMENTS "\n", *l))
                 return 0;
 
         if (startswith(l, ".include ")) {

src/shared/install.c

@@ -1699,7 +1699,7 @@ int unit_file_query_preset(UnitFileScope scope, const char *name) {
                         if (!*l)
                                 continue;
 
-                        if (strchr(COMMENTS, *l))
+                        if (strchr(COMMENTS "\n", *l))
                                 continue;
 
                         if (first_word(l, "enable")) {

src/shared/util.h

@@ -52,7 +52,7 @@ union dirent_storage {
 #define WHITESPACE " \t\n\r"
 #define NEWLINE "\n\r"
 #define QUOTES "\"\'"
-#define COMMENTS "#;\n"
+#define COMMENTS "#;"
 
 #define FORMAT_BYTES_MAX 8