Fixed 32-bit BSR

Imported-from: https://svn.code.sf.net/p/dosbox/code-0/dosbox/trunk@1230

src/cpu/core_normal/prefix_66_0f.h

@@ -336,7 +336,7 @@
 			if (value==0) {
 				SETFLAGBIT(ZF,true);
 			} else {
-				result = 35;	// Operandsize-1
+				result = 31;	// Operandsize-1
 				while ((value & 0x80000000)==0) { result--; value<<=1; }
 				SETFLAGBIT(ZF,false);
 				*rmrd = result;