accel/amdxdna: Check init_srcu_struct() return value

accel/amdxdna: Check init_srcu_struct() return value

The return value of init_srcu_struct() is currently ignored. If
initialization fails, subsequent use of hwctx_srcu may result in invalid
memory accesses.

Check the return value of init_srcu_struct() and propagate the error to
the caller.

Fixes: aac243092b70 ("accel/amdxdna: Add command execution")
Reviewed-by: Mario Limonciello (AMD) <superm1@kernel.org>
Signed-off-by: Lizhi Hou <lizhi.hou@amd.com>
Link: https://patch.msgid.link/20260707172323.539721-1-lizhi.hou@amd.com