Qt6 configure try to build also the disabled features

[Mark81]

I ran this command:

../qt5/configure -opengl es2 -sql-mysql -no-gbm -no-kms -no-xcb

but in the configure output I found:

-- Found XCB_XCB: /usr/lib/x86_64-linux-gnu/libxcb.so (found version "1.14") 
-- Could NOT find XCB_RENDER (missing: XCB_RENDER_LIBRARY XCB_RENDER_INCLUDE_DIR) (found version "")
-- Could NOT find XCB_SHAPE (missing: XCB_SHAPE_LIBRARY XCB_SHAPE_INCLUDE_DIR) (found version "")
-- Could NOT find XCB_XFIXES (missing: XCB_XFIXES_LIBRARY XCB_XFIXES_INCLUDE_DIR XCB_RENDER_FOUND XCB_SHAPE_FOUND) (found version "")
-- Could NOT find XCB_SHM (missing: XCB_SHM_LIBRARY XCB_SHM_INCLUDE_DIR) (found version "")
-- Could NOT find XCB_ATOM (missing: XCB_ATOM_LIBRARY XCB_ATOM_INCLUDE_DIR) (found version "")
-- Could NOT find XCB_AUX (missing: XCB_AUX_LIBRARY XCB_AUX_INCLUDE_DIR) (found version "")
-- Could NOT find XCB_COMPOSITE (missing: XCB_COMPOSITE_LIBRARY XCB_COMPOSITE_INCLUDE_DIR XCB_XFIXES_FOUND) (found version "")
-- Could NOT find XCB_CURSOR (missing: XCB_CURSOR_LIBRARY XCB_CURSOR_INCLUDE_DIR) (found version "")
-- Could NOT find XCB_DAMAGE (missing: XCB_DAMAGE_LIBRARY XCB_DAMAGE_INCLUDE_DIR XCB_XFIXES_FOUND) (found version "")
-- Could NOT find XCB_DPMS (missing: XCB_DPMS_LIBRARY XCB_DPMS_INCLUDE_DIR) (found version "")
-- Could NOT find XCB_DRI2 (missing: XCB_DRI2_LIBRARY XCB_DRI2_INCLUDE_DIR) (found version "")
-- Could NOT find XCB_DRI3 (missing: XCB_DRI3_LIBRARY XCB_DRI3_INCLUDE_DIR) (found version "")
-- Could NOT find XCB_EVENT (missing: XCB_EVENT_LIBRARY XCB_EVENT_INCLUDE_DIR) (found version "")
-- Could NOT find XCB_EWMH (missing: XCB_EWMH_LIBRARY XCB_EWMH_INCLUDE_DIR) (found version "")
-- Could NOT find XCB_GLX (missing: XCB_GLX_LIBRARY XCB_GLX_INCLUDE_DIR) (found version "")
...

with hundreds of other rows that report XCB errors... but why if I declared I don't want XCB?