Upgrade to palp 2.21

Also fixes build with gcc-15

Author: vbraun

build/pkgs/palp/checksums.ini

@@ -1,4 +1,4 @@
 tarball=palp-VERSION.tar.gz
-sha1=99b0d8f7c998549f9f1be6302950659ff01bac77
-sha256=0540e827b1b481a55285146377b3910991cd6bc8da67f351c15226eec6a95702
+sha1=bea363053fad1978e98d295b5b6efb74ff873ca2
+sha256=7e4a7bf219998a844c0bcce0a176e49d0743cb4b505a0e195329bf2ec196ddd7
 upstream_url=http://hep.itp.tuwien.ac.at/~kreuzer/CY/palp/palp-VERSION.tar.gz

build/pkgs/palp/package-version.txt

@@ -1 +1 @@
-2.11
+2.21

build/pkgs/palp/patches/gnu-make-3.81-compatible.patch

@@ -0,0 +1,28 @@
+Support building with GNU make 3.81
+
+The Makefile does not work on macOS
+
+    make[5]: *** No rule to make target `poly-d.x', needed by `poly.x'.
+    make[5]: *** No rule to make target `class-d.x', needed by `class.x'.
+    make[5]: *** No rule to make target `cws-d.x', needed by `cws.x'.
+    make[5]: *** No rule to make target `nef-d.x', needed by `nef.x'.
+    make[5]: *** No rule to make target `mori-d.x', needed by `mori.x'.
+    make[5]: Target `all' not remade because of errors.
+
+because the Makefile uses =-sign after the canned recipe define which
+is only supported on GNU make 3.82. And Apple, in their infinite
+wisdom, still ships the absolutely ancient 3.81
+
+
+
+--- a/GNUmakefile	2025-06-09 08:12:58
++++ b/GNUmakefile	2025-06-09 08:30:59
+@@ -41,7 +41,7 @@
+ .PHONY: cleanall
+ cleanall: ;	rm -f *.o *.x palp_* core
+ 
+-define PROG_DIM_template =
++define PROG_DIM_template
+ #
+ # Define separate build rules for every combination of PROGRAMS and
+ # DIMENSIONS. This really is necessary: we can't reuse an object file