Handle macOS target triplet (#538)

* Add diagnostic information when determiing the triplet fails in vcpkg-setup.cmake

* Set vcpkg target triplet for macOS

Author: LegalizeAdulthood

cmake/vcpkg-setup.cmake

@@ -42,7 +42,16 @@ if (NOT DEFINED VCPKG_TARGET_TRIPLET)
             endif ()
 
             set (SIMH_VCPKG_PLATFORM "linux")
+        elseif (CMAKE_SYSTEM_NAME STREQUAL "Darwin")
+            set(SIMH_VCPKG_PLATFORM "osx")
+            if (CMAKE_HOST_SYSTEM_PROCESSOR STREQUAL "arm64")
+                set(SIMH_VCPKG_ARCH "arm64")
+            else()
+                set(SIMH_VCPKG_ARCH "x64")
+            endif()
         else ()
+            message(STATUS "CMAKE_SYSTEM_NAME=${CMAKE_SYSTEM_NAME}")
+            message(STATUS "CMAKE_HOST_SYSTEM_PROCESSOR=${CMAKE_HOST_SYSTEM_PROCESSOR}")
             message(FATAL_ERROR "Could not determine VCPKG platform and system triplet."
                 "\n"
                 "(a) Are you sure that VCPKG is usable on this system? Check VCPKG_ROOT and ensure that"