phy: zynqmp: fix clock error handling in xpsgtr_phy_init()

phy: zynqmp: fix clock error handling in xpsgtr_phy_init()

Propagate clk_prepare_enable() failures to the caller instead of
returning success, and disable the reference clock on initialization
error paths to avoid leaking clock references when phy_exit() is not
called.

Fixes: 25d700833513 ("phy: xilinx: phy-zynqmp: dynamic clock support for power-save")
Signed-off-by: Radhey Shyam Pandey <radhey.shyam.pandey@amd.com>
Reviewed-by: Michal Simek <michal.simek@amd.com>
Link: https://patch.msgid.link/20260720153832.1130006-2-radhey.shyam.pandey@amd.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>