qcacld-3.0: Remove obsolete legacy cfg related files

Remove obsolete cfg_api.h and cfg_global.h files related to
legacy cfg.

Change-Id: I1978c3b44239c62b1dfb6fd59a8a25bccf277aac
CRs-Fixed: 2463744

mlme/dispatcher/inc/wlan_mlme_public_struct.h

@@ -56,6 +56,7 @@
 #define CFG_MAX_TX_POWER_2_4_LEN    128
 #define CFG_MAX_TX_POWER_5_LEN      128
 #define CFG_POWER_USAGE_MAX_LEN      4
+#define CFG_MAX_STR_LEN       256
 
 #define CFG_VALID_CHANNEL_LIST_STRING_LEN (CFG_VALID_CHANNEL_LIST_LEN * 4)
 /**