BuildSystem: using sysroot doesn't need root privileges anymore!

Sysroot is now created with fakeroot. This allows root access to be
only needed for disk image creation, since it uses loopback devices.

toolchain/Toolchain.txt

@@ -1,9 +1,19 @@
 if (NOT DEFINED ENV{BANAN_ARCH})
 	message(FATAL_ERROR "environment variable BANAN_ARCH not defined")
 endif ()
-
 set(BANAN_ARCH $ENV{BANAN_ARCH})
 
+if (NOT DEFINED ENV{BANAN_SYSROOT})
+	message(FATAL_ERROR "environment variable BANAN_SYSROOT not defined")
+endif ()
+set(BANAN_SYSROOT $ENV{BANAN_SYSROOT})
+
+if (NOT DEFINED ENV{BANAN_SYSROOT_TAR})
+	message(FATAL_ERROR "environment variable BANAN_SYSROOT_TAR not defined")
+endif ()
+set(BANAN_SYSROOT_TAR $ENV{BANAN_SYSROOT_TAR})
+
+
 set(TOOLCHAIN_PREFIX ${CMAKE_SOURCE_DIR}/toolchain/local)
 
 set(CMAKE_SYSTEM_NAME banan-os)