eqn: use intptr to silence 64-bit warning (Michael Teichgräber)

src/cmd/eqn/lex.c

diff --git a/src/cmd/eqn/lex.c b/src/cmd/eqn/lex.c
index 7ddc1f5..99a716b 100644
--- a/src/cmd/eqn/lex.c
+++ b/src/cmd/eqn/lex.c
@@ -48,7 +48,7 @@
 				ERROR "quoted string %.20s... too long", token FATAL;
 		}
 		token[sp] = '\0';
-		yylval = (int) &token[0];
+		yylval = (intptr_t)&token[0];
 		if (c == '\n')
 			ERROR "missing \" in %.20s", token WARNING;
 		return(QTEXT);