mesa/main: *TextureSubImage* generates INVALID_OPERATION on wrong target

Equivalent *TexSubImage* methods generates INVALID_ENUM.

From OpenGL 4.5 spec, section 8.6 Alternate Texture Image
Specification Commands:

   "An INVALID_ENUM error is generated by *TexSubImage* if target does
    not match the command, as shown in table 8.15."

And:

   "An INVALID_OPERATION error is generated by *TextureSubImage* if
    the effective target of texture does not match the command, as
    shown in table 8.15."

Fixes:
GL45-CTS.direct_state_access.textures_copy_errors

v2: slightly change commit summary (Samuel)

Reviewed-by: Samuel Pitoiset <samuel.pitoiset@gmail.com>

src/mesa/main/teximage.c

@@ -3939,7 +3939,7 @@ _mesa_CopyTextureSubImage1D(GLuint texture, GLint level,
 
    /* Check target (proxies not allowed). */
    if (!legal_texsubimage_target(ctx, 1, texObj->Target, true)) {
-      _mesa_error(ctx, GL_INVALID_ENUM, "%s(invalid target %s)", self,
+      _mesa_error(ctx, GL_INVALID_OPERATION, "%s(invalid target %s)", self,
                   _mesa_enum_to_string(texObj->Target));
       return;
    }
@@ -3963,7 +3963,7 @@ _mesa_CopyTextureSubImage2D(GLuint texture, GLint level,
 
    /* Check target (proxies not allowed). */
    if (!legal_texsubimage_target(ctx, 2, texObj->Target, true)) {
-      _mesa_error(ctx, GL_INVALID_ENUM, "%s(invalid target %s)", self,
+      _mesa_error(ctx, GL_INVALID_OPERATION, "%s(invalid target %s)", self,
                   _mesa_enum_to_string(texObj->Target));
       return;
    }
@@ -3990,7 +3990,7 @@ _mesa_CopyTextureSubImage3D(GLuint texture, GLint level,
 
    /* Check target (proxies not allowed). */
    if (!legal_texsubimage_target(ctx, 3, texObj->Target, true)) {
-      _mesa_error(ctx, GL_INVALID_ENUM, "%s(invalid target %s)", self,
+      _mesa_error(ctx, GL_INVALID_OPERATION, "%s(invalid target %s)", self,
                   _mesa_enum_to_string(texObj->Target));
       return;
    }