fix get_executable_path on OpenBSD; backport of
https://github.com/godotengine/godot/pull/61540

Index: drivers/unix/os_unix.cpp
--- drivers/unix/os_unix.cpp.orig
+++ drivers/unix/os_unix.cpp
@@ -497,12 +497,6 @@ String OS_Unix::get_executable_path() const {
 		return OS::get_executable_path();
 	}
 	return b;
-#elif defined(__OpenBSD__) || defined(__NetBSD__)
-	char resolved_path[MAXPATHLEN];
-
-	realpath(OS::get_executable_path().utf8().get_data(), resolved_path);
-
-	return String(resolved_path);
 #elif defined(__FreeBSD__)
 	int mib[4] = { CTL_KERN, KERN_PROC, KERN_PROC_PATHNAME, -1 };
 	char buf[MAXPATHLEN];
@@ -529,7 +523,6 @@ String OS_Unix::get_executable_path() const {
 
 	return path;
 #else
-	ERR_PRINT("Warning, don't know how to obtain executable path on this OS! Please override this function properly.");
 	return OS::get_executable_path();
 #endif
 }
