Move libc initialization functions into their own directory.

libc/Makefile

@@ -188,7 +188,7 @@ fsmarshall/fsm_mkserver.o \
 fsmarshall/fsm_recv.o \
 fsmarshall/fsm_send.o \
 grp/grent.o \
-init.o \
+init/init.o \
 libgen/basename.o \
 libgen/dirname.o \
 locale/localeconv.o \

libc/init/init.cpp

@@ -17,7 +17,7 @@
     You should have received a copy of the GNU Lesser General Public License
     along with the Sortix C Library. If not, see <http://www.gnu.org/licenses/>.
 
-    init.cpp
+    init/init.cpp
     Initializes the process by setting up the heap, signal handling, static
     memory and other useful things.