dns320l-mcu: Fix compilation with GCC 14

This fixes the following compile problem:
```
dns320l-daemon.c: In function 'main':
dns320l-daemon.c:740:18: error: implicit declaration of function 'isprint' [-Wimplicit-function-declaration]
  740 |         else if (isprint (optopt))
      |                  ^~~~~~~
dns320l-daemon.c:50:1: note: include '<ctype.h>' or provide a declaration of 'isprint'
   49 | #include "dns320l-daemon.h"
  +++ |+#include <ctype.h>
   50 |
dns320l-daemon.c:799:5: error: implicit declaration of function 'umask' [-Wimplicit-function-declaration]
  799 |     umask(0);
      |     ^~~~~
dns320l-daemon.c:864:5: error: 'return' with no value, in function returning non-void [-Wreturn-mismatch]
  864 |     return;
      |     ^~~~~~
dns320l-daemon.c:691:5: note: declared here
  691 | int main(int argc, char *argv[])
      |     ^~~~
```

Link: https://github.com/openwrt/openwrt/pull/18688
Signed-off-by: Hauke Mehrtens <hauke@hauke-m.de>

2 files changed, 51 insertions, 1 deletions

diff --git a/package/utils/dns320l-mcu/Makefile b/package/utils/dns320l-mcu/Makefile
index 9488096a16..042cce7409 100644
--- a/package/utils/dns320l-mcu/Makefile
+++ b/package/utils/dns320l-mcu/Makefile
@@ -1,7 +1,7 @@
 include $(TOPDIR)/rules.mk
 
 PKG_NAME:=dns320l-mcu
-PKG_RELEASE:=1
+PKG_RELEASE:=2
 
 PKG_SOURCE_PROTO:=git
 PKG_SOURCE_URL=https://github.com/wigyori/dns320l-daemon.git
diff --git a/package/utils/dns320l-mcu/patches/010-gcc-14-fixes.patch b/package/utils/dns320l-mcu/patches/010-gcc-14-fixes.patch
new file mode 100644
index 0000000000..dfda9c3710
--- /dev/null
+++ b/package/utils/dns320l-mcu/patches/010-gcc-14-fixes.patch
@@ -0,0 +1,50 @@
+dns320l-mcu: Fix compilation with GCC 14
+
+This fixes the following compile problem:
+```
+dns320l-daemon.c: In function 'main':
+dns320l-daemon.c:740:18: error: implicit declaration of function 'isprint' [-Wimplicit-function-declaration]
+  740 |         else if (isprint (optopt))
+      |                  ^~~~~~~
+dns320l-daemon.c:50:1: note: include '<ctype.h>' or provide a declaration of 'isprint'
+   49 | #include "dns320l-daemon.h"
+  +++ |+#include <ctype.h>
+   50 | 
+dns320l-daemon.c:799:5: error: implicit declaration of function 'umask' [-Wimplicit-function-declaration]
+  799 |     umask(0);
+      |     ^~~~~
+dns320l-daemon.c:864:5: error: 'return' with no value, in function returning non-void [-Wreturn-mismatch]
+  864 |     return;
+      |     ^~~~~~
+dns320l-daemon.c:691:5: note: declared here
+  691 | int main(int argc, char *argv[])
+      |     ^~~~
+```
+
+--- a/dns320l-daemon.c
++++ b/dns320l-daemon.c
+@@ -26,6 +26,7 @@
+ 
+ */
+ 
++#include <ctype.h>
+ #include <errno.h>
+ #include <termios.h>
+ #include <unistd.h>
+@@ -39,6 +40,7 @@
+ #include <sys/ioctl.h>
+ #include <sys/types.h>
+ #include <sys/time.h>
++#include <sys/stat.h>
+ #include <time.h>
+ #include <arpa/inet.h>
+ #include <netinet/in.h>
+@@ -861,7 +863,7 @@ int main(int argc, char *argv[])
+   if (fd < 0)
+   {
+     syslog(LOG_ERR, "error %d opening %s: %s", errno, stDaemonConfig.portName, strerror (errno));
+-    return;
++    return EXIT_FAILURE;
+   }
+ 
+   set_interface_attribs (fd, B115200, 0);  // set speed to 115,200 bps, 8n1 (no parity)