qcacld-3.0: Fix typo REAM_HASH_LEN and rename it to REALM_HASH_LEN

Fix typo REAM_HASH_LEN and rename it to REALM_HASH_LEN.

Change-Id: Ib90816753afd2cb7aa3cce65ebf4955160042a42
CRs-Fixed: 2800793

core/sme/src/csr/csr_api_roam.c

@@ -10958,7 +10958,7 @@ static void csr_update_fils_scan_filter(struct scan_filter *filter,
 						   realm_hash);
 		if (filter->fils_scan_filter.realm_check)
 			qdf_mem_copy(filter->fils_scan_filter.fils_realm,
-				     realm_hash, REAM_HASH_LEN);
+				     realm_hash, REALM_HASH_LEN);
 	}
 }