nir: Extract shader_info->cs.shared_size out of union.

It is valid for all stages, just 0 for most of them. In particular
mesh/task shaders might be using it.

Reviewed-by: Jesse Natalie <jenatali@microsoft.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/10094>

src/compiler/shader_info.h

@@ -183,6 +183,11 @@ typedef struct shader_info {
    /* SPV_KHR_float_controls: execution mode for floating point ops */
    uint16_t float_controls_execution_mode;
 
+   /**
+    * Size of shared variables accessed by compute/task/mesh shaders.
+    */
+   unsigned shared_size;
+
    uint16_t inlinable_uniform_dw_offsets[MAX_INLINABLE_UNIFORMS];
    uint8_t num_inlinable_uniforms:4;
 
@@ -377,11 +382,6 @@ typedef struct shader_info {
 
          bool zero_initialize_shared_memory;
 
-         /**
-          * Size of shared variables accessed by the compute shader.
-          */
-         unsigned shared_size;
-
          /**
           * pointer size is:
           *   AddressingModelLogical:    0    (default)