1) Refine the documentation text of 4 ini items:
gStaKeepAlivePeriod
gApKeepAlivePeriod
gChannelBondingMode5GHz
gChannelBondingMode24GHz
2) Fix a discrepancy which happens when ini cfg values
are converted from those defined in enum
eIniChanBondState to the corresponding values in
enum ePhyChanBondState.
3) Use the related APIs to setup channel bonding modes
instead of directly assigning values.
4) Remove the redundant inclusion of the following two
header files in csr_api_roam.c:
cfg_ucfg_api.h
wlan_mlme_api.h
Change-Id: I43c1e5a05bbb34952a5c7bdbde734f4014592c12
CRs-Fixed: 2416991
