Toolchain: Update build paths in CMakeToolchain.txt

Author: linusg

Toolchain/CMakeToolchain.txt

@@ -10,11 +10,13 @@ endif()
 
 set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -fno-exceptions")
 
+set(SERENITY_BUILD_DIR $ENV{SERENITY_ROOT}/Build/$ENV{SERENITY_ARCH})
+
 # where to read from/write to
-set(CMAKE_SYSROOT $ENV{SERENITY_ROOT}/Build/Root)
-set(CMAKE_STAGING_PREFIX $ENV{SERENITY_ROOT}/Build/Root/usr)
-set(CMAKE_INSTALL_PREFIX $ENV{SERENITY_ROOT}/Build/Root/usr)
-set(CMAKE_INSTALL_DATAROOTDIR $ENV{SERENITY_ROOT}/Build/Root/usr/share)
+set(CMAKE_SYSROOT ${SERENITY_BUILD_DIR}/Root)
+set(CMAKE_STAGING_PREFIX ${SERENITY_BUILD_DIR}/Root/usr)
+set(CMAKE_INSTALL_PREFIX ${SERENITY_BUILD_DIR}/Root/usr)
+set(CMAKE_INSTALL_DATAROOTDIR ${SERENITY_BUILD_DIR}/Root/usr/share)
 
 set(CMAKE_C_COMPILER $ENV{SERENITY_ARCH}-pc-serenity-gcc)
 set(CMAKE_CXX_COMPILER $ENV{SERENITY_ARCH}-pc-serenity-g++)