gnu: librecad: Fix build with boost 1.76.

Fixes <https://issues.guix.gnu.org/53694>.

* gnu/packages/patches/librecad-support-for-boost-1.76.patch: New file.
* gnu/local.mk (dist_patch_DATA): Add it.
* gnu/packages/engineering.scm (librecad)[source]: Use it.

gnu/local.mk

@@ -1408,6 +1408,7 @@ dist_patch_DATA =						\
   %D%/packages/patches/libmygpo-qt-missing-qt5-modules.patch	\
   %D%/packages/patches/libqalculate-3.8.0-libcurl-ssl-fix.patch	\
   %D%/packages/patches/libquicktime-ffmpeg.patch 		\
+  %D%/packages/patches/librecad-support-for-boost-1.76.patch	\
   %D%/packages/patches/libssh2-CVE-2019-17498.patch 		\
   %D%/packages/patches/libtar-CVE-2013-4420.patch 		\
   %D%/packages/patches/libtgvoip-disable-sse2.patch 		\

gnu/packages/engineering.scm

@@ -147,7 +147,9 @@
               (file-name (git-file-name name version))
               (sha256
                (base32
-                "08cl4935c9vznz9qdw1zgd86rn7hl64zpfayxl07x21bhf53pn24"))))
+                "08cl4935c9vznz9qdw1zgd86rn7hl64zpfayxl07x21bhf53pn24"))
+              (patches
+               (search-patches "librecad-support-for-boost-1.76.patch"))))
     (build-system qt-build-system)
     (arguments
      '(#:test-target "check"

gnu/packages/patches/librecad-support-for-boost-1.76.patch

@@ -0,0 +1,17 @@
+Upstream commit e02f3580311d50b617427652ff77988f6bd62d9d adding Boost 1.76
+compatibility.
+
+diff --git a/librecad/src/lib/engine/rs_ellipse.cpp b/librecad/src/lib/engine/rs_ellipse.cpp
+index 291f734ea..d47bf6ca4 100644
+--- a/librecad/src/lib/engine/rs_ellipse.cpp
++++ b/librecad/src/lib/engine/rs_ellipse.cpp
+@@ -48,6 +48,9 @@
+ #include <boost/version.hpp>
+ #include <boost/math/tools/roots.hpp>
+ #include <boost/math/special_functions/ellint_2.hpp>
++#if BOOST_VERSION > 104500
++#include <boost/math/tools/tuple.hpp>
++#endif
+ #endif
+ 
+ namespace{