external/lua: update to Lua 5.4.7

Update the version of Lua included with Callisto to Lua 5.4.7.
Re-generate patches to apply cleanly on top of Lua 5.4.7 sources.

Fixes: https://todo.sr.ht/~jeremy/callisto/8

external/lua/patches/lua-5.4.7-oslib-hostname.diff

@@ -0,0 +1,59 @@
+--- loslib.c
++++ loslib.c
+@@ -4,6 +4,12 @@
+ ** See Copyright Notice in lua.h
+ */
+ 
++/***
++ * Operating system related facilities.
++ *
++ * @module os
++ */
++
+ #define loslib_c
+ #define LUA_LIB
+ 
+@@ -14,6 +20,7 @@
+ #include <locale.h>
+ #include <stdlib.h>
+ #include <string.h>
++#include <unistd.h>
+ #include <time.h>
+ 
+ #include "lua.h"
+@@ -403,6 +410,27 @@
+   return 0;
+ }
+ 
++#ifndef HOST_NAME_MAX
++#define HOST_NAME_MAX 256 /* according to POSIX */
++#endif
++
++/***
++ * Returns the system hostname.
++ *
++ * @function hostname
++ * @usage local hostname = os.hostname()
++ */
++static int
++os_hostname(lua_State *L)
++{
++	char buffer[HOST_NAME_MAX];
++
++	gethostname(buffer, HOST_NAME_MAX); /* get hostname */
++	lua_pushstring(L, buffer);
++
++    return 1;
++}
++
+ 
+ static const luaL_Reg syslib[] = {
+   {"clock",     os_clock},
+@@ -411,6 +439,7 @@
+   {"execute",   os_execute},
+   {"exit",      os_exit},
+   {"getenv",    os_getenv},
++  {"hostname",  os_hostname},
+   {"remove",    os_remove},
+   {"rename",    os_rename},
+   {"setlocale", os_setlocale},