gh-35743: gc: update to 8.2.4
    
### 📚 Description

Update gc package to the latest stable upstream release.

More details:
* Remove --enable-shared --disable-static from configure options.
* Remove -DUSE_MMAP -DUSE_MUNMAP from CFLAGS.
* Update license and upstream contact info.

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### ⌛ Dependencies

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URL: #35743
Reported by: Ivan Maidanski
Reviewer(s):

Author: Release Manager

build/pkgs/gc/SPKG.rst

@@ -6,25 +6,24 @@ Description
 
 The Boehm-Demers-Weiser conservative garbage collector.
 
+
 License
 -------
 
--  Permissive BSD + GPL 2.0+
+-  MIT-style (https://github.com/ivmai/bdwgc/blob/master/LICENSE)
 
 
 Upstream Contact
 ----------------
 
-Webpage: http://www.hboehm.info/gc/
+-  Ivan Maidanski
+
+Webpage:
+-  https://github.com/ivmai/bdwgc/
+-  https://www.hboehm.info/gc/
 
-Email List: [email protected]
 
 Special Update/Build Instructions
 ---------------------------------
 
 None.
-
-Patches
-~~~~~~~
-
--  cygwin64.patch: let libgc build on Cygwin64.

build/pkgs/gc/checksums.ini

@@ -1,5 +1,5 @@
 tarball=gc-VERSION.tar.gz
-sha1=4b8b24534f469b64ff4bc2332a9bdf8bef8bf1d4
-md5=67a5093e2f9f381bd550aa891d00b54b
-cksum=121524068
+sha1=41c88cbc4bc9bf76e1a95a1500ea5b0360bc4f55
+md5=8901a6ed29ac35842420054772ea3441
+cksum=4201205407
 upstream_url=https://github.com/ivmai/bdwgc/releases/download/vVERSION/gc-VERSION.tar.gz

build/pkgs/gc/package-version.txt

@@ -1 +1 @@
-8.0.4
+8.2.4

build/pkgs/gc/spkg-install.in

@@ -4,9 +4,7 @@ GC_CONFIGURE="--enable-large-config"
 
 if [ "$UNAME" = "CYGWIN" ]; then
     # See https://github.com/sagemath/sage/issues/22694
-    GC_CONFIGURE="$GC_CONFIGURE --enable-threads=posix --enable-handle-fork --enable-shared --disable-static"
-    # Force use of mmap on Cygwin https://github.com/sagemath/sage/issues/23973
-    export CFLAGS="$CFLAGS -DUSE_MMAP -DUSE_MUNMAP"
+    GC_CONFIGURE="$GC_CONFIGURE --enable-threads=posix --enable-handle-fork"
 fi
 
 sdh_configure $GC_CONFIGURE