[openwrt/openwrt] ead: replace legacy RETSIGTYPE with void in signal handler

[LEDE Commits]

nick pushed a commit to openwrt/openwrt.git, branch main:
https://git.openwrt.org/6719bf56727f873dbd62d63fe023b4cca64fb786

commit 6719bf56727f873dbd62d63fe023b4cca64fb786
Author: Nick Hainke <vincent at systemli.org>
AuthorDate: Tue Aug 5 18:21:55 2025 +0200

    ead: replace legacy RETSIGTYPE with void in signal handler
    
    The RETSIGTYPE macro was historically used for signal handler return types,
    defaulting to int on some legacy systems. This is no longer needed,
    so we now use void as the return type.
    
    Fixes a compiler error:
      error: assignment to 'void (*)(int)' from incompatible pointer type 'int (*)()' [-Wincompatible-pointer-types]
    
    Link: https://github.com/openwrt/openwrt/pull/19681
    Signed-off-by: Nick Hainke <vincent at systemli.org>
---
 package/network/services/ead/src/tinysrp/t_getpass.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/package/network/services/ead/src/tinysrp/t_getpass.c b/package/network/services/ead/src/tinysrp/t_getpass.c
index 6ae7fca4de..a7d571d5de 100644
--- a/package/network/services/ead/src/tinysrp/t_getpass.c
+++ b/package/network/services/ead/src/tinysrp/t_getpass.c
@@ -44,7 +44,7 @@ static  struct  sigaction sigact;
 #endif
 
 /*ARGSUSED*/
-static RETSIGTYPE
+static void
 sig_catch (sig)
 int     sig;
 {