phy: qcom: m31-eusb2: fix match data santity check

phy: qcom: m31-eusb2: fix match data santity check

The device_get_match_data() helper returns NULL if a new entry is ever
added without corresponding match data.

Fixes: 9c8504861cc4 ("phy: qcom: Add M31 based eUSB2 PHY driver")
Cc: Wesley Cheng <quic_wcheng@quicinc.com>
Cc: Melody Olvera <melody.olvera@oss.qualcomm.com>
Signed-off-by: Johan Hovold <johan+linaro@kernel.org>
Reviewed-by: Neil Armstrong <neil.armstrong@linaro.org>
Link: https://lore.kernel.org/r/20250617080503.11262-1-johan+linaro@kernel.org
Signed-off-by: Vinod Koul <vkoul@kernel.org>