Include vcpkg patch

[bernhardmgruber]

vcpkg contains the following patch when building/installing Vc:

diff --git a/cmake/VcConfig.cmake.in b/cmake/VcConfig.cmake.in
index 36de476..5cb0e5b 100644
--- a/cmake/VcConfig.cmake.in
+++ b/cmake/VcConfig.cmake.in
@@ -4,7 +4,7 @@
 set_and_check(@PROJECT_NAME@_INSTALL_DIR @PACKAGE_CMAKE_INSTALL_PREFIX@)
 set_and_check(@PROJECT_NAME@_INCLUDE_DIR @PACKAGE_CMAKE_INSTALL_PREFIX@/include)
 set_and_check(@PROJECT_NAME@_LIB_DIR @PACKAGE_CMAKE_INSTALL_PREFIX@/lib@LIB_SUFFIX@)
-set_and_check(@PROJECT_NAME@_CMAKE_MODULES_DIR ${@PROJECT_NAME@_LIB_DIR}/cmake/Vc)
+set_and_check(@PROJECT_NAME@_CMAKE_MODULES_DIR @PACKAGE_CMAKE_INSTALL_PREFIX@/share/vc)
 set(@PROJECT_NAME@_VERSION_STRING "@PROJECT_VERSION@")
 
 ### Setup @PROJECT_NAME@ defaults
@@ -20,7 +20,7 @@ list(APPEND @PROJECT_NAME@_ALL_FLAGS ${@PROJECT_NAME@_COMPILE_FLAGS})
 list(APPEND @PROJECT_NAME@_ALL_FLAGS ${@PROJECT_NAME@_ARCHITECTURE_FLAGS})
 
 ### Import targets
-include("@PACKAGE_CMAKE_INSTALL_PREFIX@/@PACKAGE_INSTALL_DESTINATION@/@[email protected]")
+include(${@PROJECT_NAME@_CMAKE_MODULES_DIR}/@[email protected])
 
 ### Define @PROJECT_NAME@_LIBRARIES for backwards compatibility
 get_target_property(vc_lib_location @PROJECT_NAME@::Vc INTERFACE_LOCATION)

If the changes are correct, we should include the patch.

[dennisklein]

This patch is only correct when combined with this line: https://github.com/microsoft/vcpkg/blob/62d01b70df227850b728f5050418b917ad6d2b32/ports/vc/portfile.cmake#L19

Basically, CMake allows a lot of locations for the CMake package to be installed to: https://cmake.org/cmake/help/latest/command/find_package.html#config-mode-search-procedure. Usually, packagers will have to shift the location around in order to satisfy their own polices or some operating system's policy which may be stricter than CMake in this aspect.

Vc could certainly adopt to install its CMake package to <prefix>/share/vc by default or to make

Vc/CMakeLists.txt

Lines 213 to 215 in d4b8109

	set(PACKAGE_INSTALL_DESTINATION
	lib${LIB_SUFFIX}/cmake/${PROJECT_NAME}
	)

configurable via e.g. -DVc_PACKAGE_INSTALL_DESTINATION=... to ease a package maintainer's life.