In the case of Station connects to AP with narrower bandwidth at beginning.
And later the AP changes the bandwidth to winder bandwidth, the AP will
beacon with wider bandwidth IE, eg VHT20->VHT40->VHT80 or VHT40->VHT80.

Since the supported BANDWIDTH will be limited by the PHYMODE, so while
Station receives the bandwidth change request, it will also need to
reconfigure the PHYMODE setting to firmware instead of just configuring
the BANDWIDTH info, otherwise it'll trigger a firmware crash with
non-support bandwidth.

The issue was observed in WLAN.RM.4.4.1-00051-QCARMSWP-1, QCA6174 with
below scenario:

AP xxx changed bandwidth, new config is 5200 MHz, width 2 (5190/0 MHz)
disconnect from AP xxx for new auth to yyy
RX ReassocResp from xxx (capab=0x1111 status=0 aid=102)
associated

....

AP xxx changed bandwidth, new config is 5200 MHz, width 2 (5190/0 MHz)
AP xxx changed bandwidth, new config is 5200 MHz, width 3 (5210/0 MHz)

....

firmware register dump:
[00]: 0x05030000 0x000015B3 0x00987291 0x00955B31
[04]: 0x00987291 0x00060730 0x00000004 0x00000001
[08]: 0x004089F0 0x00955A00 0x000A0B00 0x00400000
[12]: 0x00000009 0x00000000 0x00952CD0 0x00952CE6
[16]: 0x00952CC4 0x0098E25F 0x00000000 0x0091080D
[20]: 0x40987291 0x0040E7A8 0x00000000 0x0041EE3C
[24]: 0x809ABF05 0x0040E808 0x00000000 0xC0987291
[28]: 0x809A650C 0x0040E948 0x0041FE40 0x004345C4
[32]: 0x809A5C63 0x0040E988 0x0040E9AC 0x0042D1A8
[36]: 0x8091D252 0x0040E9A8 0x00000002 0x00000001
[40]: 0x809FDA9D 0x0040EA58 0x0043D554 0x0042D554
[44]: 0x809F8B22 0x0040EA78 0x0043D554 0x00000001
[48]: 0x80911210 0x0040EAC8 0x00000010 0x004041D0
[52]: 0x80911154 0x0040EB28 0x00400000 0x00000000
[56]: 0x8091122D 0x0040EB48 0x00000000 0x00400600
Reported-by: Rouven Czerwinski <rouven@czerwinskis.de>
Tested-by: Timur Kristóf <timur.kristof@gmail.com>
Signed-off-by: Ryan Hsu <ryanhsu@codeaurora.org>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>