Kernel: Add new sysconf option _SC_GETGR_R_SIZE_MAX

Author: https://github.com/hanaa12G
Commit: 7abda6a36f
Pull-request: https://github.com/SerenityOS/serenity/pull/22416
Reviewed-by: https://github.com/ADKaster ✅

Kernel/API/POSIX/unistd.h

@@ -40,6 +40,7 @@ enum {
     _SC_TTY_NAME_MAX,
     _SC_PAGESIZE,
     _SC_GETPW_R_SIZE_MAX,
+    _SC_GETGR_R_SIZE_MAX,
     _SC_CLK_TCK,
     _SC_SYMLOOP_MAX,
     _SC_MAPPED_FILES,
@@ -57,6 +58,7 @@ enum {
 #define _SC_HOST_NAME_MAX _SC_HOST_NAME_MAX
 #define _SC_TTY_NAME_MAX _SC_TTY_NAME_MAX
 #define _SC_GETPW_R_SIZE_MAX _SC_GETPW_R_SIZE_MAX
+#define _SC_GETGR_R_SIZE_MAX _SC_GETGR_R_SIZE_MAX
 #define _SC_CLK_TCK _SC_CLK_TCK
 #define _SC_SYMLOOP_MAX _SC_SYMLOOP_MAX
 #define _SC_MAPPED_FILES _SC_MAPPED_FILES