temp/conky: fix build with current Alpine
Fix for https://builds.sr.ht/~postmarketos/job/1381560#task-pmbootstrap_build-660:
ninja: job failed: /usr/lib/ccache/bin/g++ -D_LARGEFILE64_SOURCE -D_POSIX_C_SOURCE=200809L -I/home/pmos/build/src/conky-1.20.1/3rdparty/toluapp/include -I/home/pmos/build/src/conky-1.20.1/build -I/usr/include/freetype2 -I/usr/include/pango-1.0 -I/usr/include/cairo -I/usr/include/pixman-1 -I/usr/include/libmount -I/usr/include/blkid -I/usr/include/fribidi -I/usr/include/harfbuzz -I/usr/include/libpng16 -I/usr/include/glib-2.0 -I/usr/lib/glib-2.0/include -I/usr/include/lua5.4 -I/usr/include/libxml2 -I/home/pmos/build/src/conky-1.20.1/build/data -I/home/pmos/build/src/conky-1.20.1/build/src -Os -fstack-clash-protection -Wformat -Werror=format-security -D_GLIBCXX_ASSERTIONS=1 -D_LIBCPP_ENABLE_THREAD_SAFETY_ANNOTATIONS=1 -D_LIBCPP_ENABLE_HARDENED_MODE=1 -fno-plt -Os -DNDEBUG -std=c++17 -MD -MT src/CMakeFiles/conky.dir/x11.cc.o -MF src/CMakeFiles/conky.dir/x11.cc.o.d -o src/CMakeFiles/conky.dir/x11.cc.o -c /home/pmos/build/src/conky-1.20.1/src/x11.cc
/home/pmos/build/src/conky-1.20.1/src/x11.cc: In function 'void propagate_xinput_event(const conky::xi_event_data*)':
/home/pmos/build/src/conky-1.20.1/src/x11.cc:1397:20: error: 'remove_if' is not a member of 'std'; did you mean 'remove_cv'?
1397 | auto it = std::remove_if(below.begin(), below.end(),
| ^~~~~~~~~
| remove_cv
/home/pmos/build/src/conky-1.20.1/src/x11.cc: In function 'void propagate_x11_event(XEvent&, const void*)':
/home/pmos/build/src/conky-1.20.1/src/x11.cc:1456:20: error: 'remove_if' is not a member of 'std'; did you mean 'remove_cv'?
1456 | auto it = std::remove_if(below.begin(), below.end(),
| ^~~~~~~~~
| remove_cv
ninja: subcommand failed