usb: dwc3: st: Rely on child's compatible instead of name

To ensure that child node is found, don't rely on child's node name
which can take different value, but on child's compatible name.

Fixes: f5c5936d

 ("usb: dwc3: st: Fix node's child name")
Cc: stable <stable@kernel.org>
Cc: Jerome Audu <jerome.audu@st.com>
Reported-by: Felipe Balbi <felipe@balbi.sh>
Signed-off-by: Patrice Chotard <patrice.chotard@foss.st.com>
Link: https://lore.kernel.org/r/20220930142018.890535-1-patrice.chotard@foss.st.com


Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>