Fix resolving symbol names on ARM.

On ARM, binutils are adding '$a' symbols in the symbol table for
every function (in addition to normal symbol). When gprof(1) looks
up symbol name, it often reads '$a' instead of proper function name,
because it find it first. With this fix, when read symbol name
begins with '$' and previous symbol has the same address, it will
use previous symbol name (which is proper function name).

Obtained from:	Semihalf

usr.bin/gprof/lookup.c

@@ -66,6 +66,12 @@ nllookup( address )
 		    printf( "[nllookup] %d (%d) probes\n" , probes , nname-1 );
 		}
 #	    endif /* DEBUG */
+#if defined(__arm__)
+	if (nl[middle].name[0] == '$' &&
+	    nl[middle-1].value == nl[middle].value)
+		middle--;
+#endif
+
 	    return &nl[ middle ];
 	}
 	if ( nl[ middle ].value > address ) {