staging: rtl8192e: Fix smatch error and warning in rtl_core.c

Smatch shows the following errors:

  CHECK   drivers/staging/rtl8192e/rtl_core.c
drivers/staging/rtl8192e/rtl_core.c +600 rtl8192_qos_activate(7) warn: variable dereferenced before check 'priv'
drivers/staging/rtl8192e/rtl_core.c +1345 rtl8192_init(40) warn: 'dev->irq' was not released on error
drivers/staging/rtl8192e/rtl_core.c +2120 rtl8192_alloc_rx_desc_ring(43) error: potential null derefence 'entry'.
drivers/staging/rtl8192e/rtl_core.c +3010 rtl8192_pci_probe(153) warn: 'pmem_start' was not released on error

Signed-off-by: Larry Finger <Larry.Finger@lwfinger.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>