staging: rtl8188eu: Fix module loading from tasklet for CCMP encryption

Commit 6bd082a ("staging:r8188eu: use lib80211 CCMP decrypt")
causes scheduling while atomic bugs followed by a hard freeze whenever
the driver tries to connect to a CCMP-encrypted network. Experimentation
showed that the freezes were eliminated when module lib80211 was
preloaded, which can be forced by calling lib80211_get_crypto_ops()
directly rather than indirectly through try_then_request_module().
With this change, no BUG messages are logged.

Fixes: 6bd082a ("staging:r8188eu: use lib80211 CCMP decrypt")
Cc: Stable <stable@vger.kernel.org> # v4.17+
Reported-and-tested-by: Michael Straube <straube.linux@gmail.com>
Cc: Ivan Safonov <insafonov@gmail.com>
Signed-off-by: Larry Finger <Larry.Finger@lwfinger.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/staging/rtl8188eu/core/rtw_security.c

@@ -1291,7 +1291,7 @@ u32 rtw_aes_decrypt(struct adapter *padapter, u8 *precvframe)
 			struct sk_buff *skb = ((struct recv_frame *)precvframe)->pkt;
 			void *crypto_private = NULL;
 			u8 *key, *pframe = skb->data;
-			struct lib80211_crypto_ops *crypto_ops = try_then_request_module(lib80211_get_crypto_ops("CCMP"), "lib80211_crypt_ccmp");
+			struct lib80211_crypto_ops *crypto_ops = lib80211_get_crypto_ops("CCMP");
 			struct security_priv *psecuritypriv = &padapter->securitypriv;
 			char iv[8], icv[8];