*: convert amenable fdopen calls to take_fdopen

Mechanical change to eliminate some cruft by using the
new take_fdopen{_unlocked}() wrappers where trivial.

src/shared/ask-password-api.c

@@ -791,14 +791,12 @@ int ask_password_agent(
 
         (void) fchmod(fd, 0644);
 
-        f = fdopen(fd, "w");
+        f = take_fdopen(&fd, "w");
         if (!f) {
                 r = -errno;
                 goto finish;
         }
 
-        fd = -1;
-
         signal_fd = signalfd(-1, &mask, SFD_NONBLOCK|SFD_CLOEXEC);
         if (signal_fd < 0) {
                 r = -errno;

src/shared/dissect-image.c

@@ -1541,14 +1541,12 @@ int dissected_image_acquire_metadata(DissectedImage *m) {
 
                 fds[2*k+1] = safe_close(fds[2*k+1]);
 
-                f = fdopen(fds[2*k], "r");
+                f = take_fdopen(&fds[2*k], "r");
                 if (!f) {
                         r = -errno;
                         goto finish;
                 }
 
-                fds[2*k] = -1;
-
                 switch (k) {
 
                 case META_HOSTNAME:

src/shared/install.c

@@ -1280,10 +1280,9 @@ static int unit_file_load(
         if (r < 0)
                 return r;
 
-        f = fdopen(fd, "r");
+        f = take_fdopen(&fd, "r");
         if (!f)
                 return -errno;
-        fd = -1;
 
         /* c is only needed if we actually load the file (it's referenced from items[] btw, in case you wonder.) */
         assert(c);

src/shared/os-util.c

@@ -3,6 +3,7 @@
 #include "alloc-util.h"
 #include "env-file.h"
 #include "fd-util.h"
+#include "fileio.h"
 #include "fs-util.h"
 #include "macro.h"
 #include "os-util.h"
@@ -76,10 +77,9 @@ int fopen_os_release(const char *root, char **ret_path, FILE **ret_file) {
         if (r < 0)
                 return r;
 
-        f = fdopen(fd, "r");
+        f = take_fdopen(&fd, "r");
         if (!f)
                 return -errno;
-        fd = -1;
 
         *ret_file = f;