Move 64bit division from avr32 to generic lib

Move the 64bit division from lib_avr32 to lib_generic. With this, all
boards can do_div/__div64_32 if needed, not only avr one. Code is put
to lib_generic, so no larger memory footprint if not used. No code
modifications. Thanks for proposal by HÃ¥vard Skinnemoen.

Signed-off-by: Dirk Behme <dirk.behme@gmail.com>
diff --git a/lib_generic/Makefile b/lib_generic/Makefile
index b2091c5..bf37752 100644
--- a/lib_generic/Makefile
+++ b/lib_generic/Makefile
@@ -27,7 +27,7 @@
 
 COBJS	= bzlib.o bzlib_crctable.o bzlib_decompress.o \
 	  bzlib_randtable.o bzlib_huffman.o \
-	  crc32.o ctype.o display_options.o ldiv.o sha1.o \
+	  crc32.o ctype.o display_options.o div64.o ldiv.o sha1.o \
 	  string.o vsprintf.o zlib.o
 
 SRCS 	:= $(COBJS:.o=.c)