ANDROID: trusty-ipc: fix wrong format string

Fix the following warning:

    drivers/trusty/trusty-ipc.c: In function ‘dn_share_fd’:
    drivers/trusty/trusty-ipc.c:1154:17: warning: format ‘%d’ expects argument of type ‘int’, but argument 4 has type ‘long unsigned int’ [-Wformat=]
     1154 |    dev_dbg(dev, "shmem_getpage(%d) failed: %d\n", pg_idx,

Change-Id: I1fc45d877239ba7ead42b876db794dc14e57ebc1
Signed-off-by: Eric Biggers <ebiggers@google.com>