gengetopt: backport patch fixing support for c++17

Backport patch fixing support for c++17 that got merged upstream in
gengetopt.

Signed-off-by: Christian Marangi <ansuelsmth@gmail.com>

tools/gengetopt/patches/001-gm_utils.cpp-Call-clear-instead-of-empty.patch

@@ -0,0 +1,25 @@
+From bfba6445a778007f40af5cbfbe725e12c0fcafc6 Mon Sep 17 00:00:00 2001
+From: Tomas Volf <~@wolfsden.cz>
+Date: Tue, 5 Mar 2024 22:25:20 +0100
+Subject: [PATCH] gm_utils.cpp: Call clear instead of empty.
+
+Since the intention seem to be to erase the next word, I believe calling empty
+was a mistake and it should have been clear.  Empty does nothing in this
+context.
+
+* src/gm_utils.cpp (wrap_cstr): Call clear.
+---
+ src/gm_utils.cpp | 2 +-
+ 1 file changed, 1 insertion(+), 1 deletion(-)
+
+--- a/src/gm_utils.cpp
++++ b/src/gm_utils.cpp
+@@ -311,7 +311,7 @@ void wrap_cstr(string& wrapped, unsigned
+             // trim leading spaces
+             std::size_t pos = next_word.find_first_not_of(' ');
+             if( pos == std::string::npos )
+-                next_word.empty();
++                next_word.clear();
+             else if( pos )
+                 next_word.erase( 0, pos );
+