glsl2: Fix expression type in builtin tan().

Fixes glsl-fs-tan-1.
diff --git a/src/glsl/builtin_function.cpp b/src/glsl/builtin_function.cpp
index eade72a..a8acff4 100644
--- a/src/glsl/builtin_function.cpp
+++ b/src/glsl/builtin_function.cpp
@@ -2097,17 +2097,17 @@
    "   (signature vec2\n"
    "     (parameters\n"
    "       (declare (in) vec2 angle))\n"
-   "     ((return (expression float / (expression float sin (var_ref angle)) (expression vec2 cos (var_ref angle))))))\n"
+   "     ((return (expression vec2 / (expression vec2 sin (var_ref angle)) (expression vec2 cos (var_ref angle))))))\n"
    "\n"
    "   (signature vec3\n"
    "     (parameters\n"
    "       (declare (in) vec3 angle))\n"
-   "     ((return (expression float / (expression float sin (var_ref angle)) (expression vec3 cos (var_ref angle))))))\n"
+   "     ((return (expression vec3 / (expression vec3 sin (var_ref angle)) (expression vec3 cos (var_ref angle))))))\n"
    "\n"
    "   (signature vec4\n"
    "     (parameters\n"
    "       (declare (in) vec4 angle))\n"
-   "     ((return (expression float / (expression float sin (var_ref angle)) (expression vec4 cos (var_ref angle))))))\n"
+   "     ((return (expression vec4 / (expression vec4 sin (var_ref angle)) (expression vec4 cos (var_ref angle))))))\n"
    "))\n"
 };