[base] Use more common `FT_MSB' implementation with masks.

* src/base/ftcalc.c (FT_MSB): Updated.
diff --git a/ChangeLog b/ChangeLog
index 4e26bde..9a38f8f 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,9 @@
+2014-10-01  Alexei Podtelezhnikov  <apodtele@gmail.com>
+
+	[base] Use more common `FT_MSB' implementation with masks.
+
+	* src/base/ftcalc.c (FT_MSB): Updated.
+
 2014-09-30  Alexei Podtelezhnikov  <apodtele@gmail.com>
 
 	[base] Clean up.