lrzsz: update to support clang 16

Closes: https://trac.macports.org/ticket/70755

comms/lrzsz/Portfile

@@ -5,16 +5,13 @@ PortSystem          1.0
 name                lrzsz
 version             0.12.20
 revision            4
+
 categories          comms
 license             GPL-2+
 maintainers         nomaintainer
-platforms           darwin
-
 description         free XMODEM/YMODEM/ZMODEM implementation
-
 long_description    ${name} is a Unix communication package providing the \
                     XMODEM, YMODEM, and ZMODEM file transfer protocols.
-
 homepage            https://ohse.de/uwe/software/lrzsz.html
 master_sites        https://ohse.de/uwe/releases/
 
@@ -26,6 +23,14 @@ configure.args      --program-transform-name=s/l// \
                     --mandir=${prefix}/share/man \
                     --disable-nls
 
+# workaround for clang 16+
+if {[string match *clang* ${configure.cc}]} {
+    configure.cflags-append \
+                    -Wno-implicit-int \
+                    -Wno-error=unknown-warning-option \
+                    -Wno-unknown-warning-option
+}
+
 patchfiles          implicit.patch \
                     patch-man-lrz.diff \
                     patch-man-lsz.diff \