bug#35232: webkitgtk-2.24.1 fails to build on i686, but earlier versions work

[Mark H Weaver <mhw@netris.org>]

Hydra failed to build webkitgtk-2.24.1 on i686-linux, saying "SSE2
support is required to compile WebKit".

  https://hydra.gnu.org/build/3439652

See below for the tail of the build log.  Note that earlier versions of
webkitgtk built successfully on i686-linux, including 2.24.0:

  https://hydra.gnu.org/job/gnu/master/webkitgtk-2.24.0.i686-linux

Removing support for i686, or even for systems without SSE2, seems like
an odd thing for upstream to do in a point release.  Is it truly the
case, or can we fix this with a change in configuration?

       Mark


--8<---------------cut here---------------start------------->8---
-- Performing Test HAVE_SSE2_EXTENSIONS
-- Performing Test HAVE_SSE2_EXTENSIONS - Failed
CMake Error at CMakeLists.txt:115 (message):
  SSE2 support is required to compile WebKit


-- Configuring incomplete, errors occurred!
See also "/tmp/guix-build-webkitgtk-2.24.1.drv-0/build/CMakeFiles/CMakeOutput.log".
See also "/tmp/guix-build-webkitgtk-2.24.1.drv-0/build/CMakeFiles/CMakeError.log".
Backtrace:
           4 (primitive-load "/gnu/store/1508pywp2hnfgqqg4dm5kihfvcg…")
In ice-9/eval.scm:
   191:35  3 (_ _)
In srfi/srfi-1.scm:
   863:16  2 (every1 #<procedure 82facb0 at /gnu/store/8993x11f4bf3…> …)
In /gnu/store/8993x11f4bf3lb0il9gnh85kjjikcf4b-module-import/guix/build/gnu-build-system.scm:
   799:28  1 (_ _)
In /gnu/store/8993x11f4bf3lb0il9gnh85kjjikcf4b-module-import/guix/build/utils.scm:
    616:6  0 (invoke _ . _)

/gnu/store/8993x11f4bf3lb0il9gnh85kjjikcf4b-module-import/guix/build/utils.scm:616:6: In procedure invoke:
Throw to key `srfi-34' with args `(#<condition &invoke-error [program: "cmake" arguments: ("../webkitgtk-2.24.1" "-DCMAKE_BUILD_TYPE=Release" "-DCMAKE_INSTALL_PREFIX=/gnu/store/qyc9fdv73bcil59q0cb26m2pb4lkpryb-webkitgtk-2.24.1" "-DCMAKE_INSTALL_LIBDIR=lib" "-DCMAKE_INSTALL_RPATH_USE_LINK_PATH=TRUE" "-DCMAKE_INSTALL_RPATH=/gnu/store/qyc9fdv73bcil59q0cb26m2pb4lkpryb-webkitgtk-2.24.1/lib" "-DCMAKE_VERBOSE_MAKEFILE=ON" "-DPORT=GTK" "-DENABLE_GTKDOC=ON" "-DLIB_INSTALL_DIR=/gnu/store/qyc9fdv73bcil59q0cb26m2pb4lkpryb-webkitgtk-2.24.1/lib" "-DUSE_GSTREAMER_GL=OFF" "-DUSE_WOFF2=OFF") exit-status: 1 term-signal: #f stop-signal: #f] 8181fc0>)'.
builder for `/gnu/store/gkfdcw6fy9ban2ids5f5gv5ffgrsqnik-webkitgtk-2.24.1.drv' failed with exit code 1
@ build-failed /gnu/store/gkfdcw6fy9ban2ids5f5gv5ffgrsqnik-webkitgtk-2.24.1.drv - 1 builder for `/gnu/store/gkfdcw6fy9ban2ids5f5gv5ffgrsqnik-webkitgtk-2.24.1.drv' failed with exit code 1
--8<---------------cut here---------------end--------------->8---