OpenGL: set geometry shader input length implicitly

Input array length is implicitly set at link time, based on the geometry
shader's layout. Specifying the wrong value here is an error; specifying
no value is the same as getting it right. (inspired by a recent codegen
change)

intern/opensubdiv/gpu_shader_opensubd_display.glsl

@@ -81,7 +81,7 @@ uniform int osd_active_uv_offset;
 
 in block {
 	VertexData v;
-} inpt[4];
+} inpt[];
 
 #define INTERP_FACE_VARYING_2(result, fvarOffset, tessCoord)  \
 	{ \

source/blender/gpu/shaders/gpu_shader_fx_dof_hq_geo.glsl

@@ -17,12 +17,12 @@ uniform sampler2D cocbuffer;
 
 /* initial uv coordinate */
 #if __VERSION__ < 130
-  varying in vec2 uvcoord[1];
+  varying in vec2 uvcoord[];
   varying out vec2 particlecoord;
   varying out vec4 color;
   #define textureLod texture2DLod
 #else
-  in vec2 uvcoord[1];
+  in vec2 uvcoord[];
   out vec2 particlecoord;
   out vec4 color;
 #endif

source/blender/gpu/shaders/gpu_shader_geometry.glsl

@@ -8,7 +8,7 @@ uniform int osd_active_uv_offset;
 
 in block {
 	VertexData v;
-} inpt[4];
+} inpt[];
 
 /* compatibility */
 out vec3 varnormal;