ld: fix Plan 9 symbol table

Static symbols were not being marked as such.

I also made the 'z' symbols use the first byte of
the name instead of an explicit NUL so that if
the symbol table format is ever changed, the only
place that would need updating is addhist().

R=rsc
CC=golang-dev
https://golang.org/cl/4366047

src/cmd/ld/symtab.c

@@ -140,29 +140,25 @@ void
 putplan9sym(Sym *x, char *s, int t, vlong addr, vlong size, int ver, Sym *go)
 {
 	int i;
-		
+
 	switch(t) {
 	case 'T':
-	case 't':
 	case 'L':
-	case 'l':
 	case 'D':
-	case 'd':
 	case 'B':
-	case 'b':
+		if(ver)
+			t += 'a' - 'A';
 	case 'a':
 	case 'p':
-	
 	case 'f':
 	case 'z':
 	case 'Z':
-		
 	case 'm':
 		lputb(addr);
 		cput(t+0x80); /* 0x80 is variable length */
-		
+
 		if(t == 'z' || t == 'Z') {
-			cput(0);
+			cput(s[0]);
 			for(i=1; s[i] != 0 || s[i+1] != 0; i += 2) {
 				cput(s[i]);
 				cput(s[i+1]);
@@ -172,19 +168,17 @@ putplan9sym(Sym *x, char *s, int t, vlong addr, vlong size, int ver, Sym *go)
 			i++;
 		} else {
 			/* skip the '<' in filenames */
-			if(t=='f')
+			if(t == 'f')
 				s++;
-			
 			for(i=0; s[i]; i++)
 				cput(s[i]);
 			cput(0);
 		}
-		
 		symsize += 4 + 1 + i + 1;
 		break;
 	default:
 		return;
-	};	
+	};
 }
 
 void