crc16: Move standard CRC-16 implementation from ubifs to lib

This implementation provides standard CRC-16 algorithm with polynomial
x^16 + x^15 + x^2 + 1.

Signed-off-by: Pali Rohár <pali@kernel.org>
Reviewed-by: Stefan Roese <sr@denx.de>
diff --git a/fs/ubifs/Makefile b/fs/ubifs/Makefile
index 64d6447..631ba5f 100644
--- a/fs/ubifs/Makefile
+++ b/fs/ubifs/Makefile
@@ -9,5 +9,5 @@
 
 obj-y := ubifs.o io.o super.o sb.o master.o lpt.o
 obj-y += lpt_commit.o scan.o lprops.o
-obj-y += tnc.o tnc_misc.o debug.o crc16.o budget.o
+obj-y += tnc.o tnc_misc.o debug.o budget.o
 obj-y += log.o orphan.o recovery.o replay.o gc.o