mwlwifi: add pending patch to fix compilation with kernel 6.6.109+

mwlwifi: add pending patch to fix compilation with kernel 6.6.109+

Building against recent kernel versions (noticed with 6.12) and -Werror
can fail because a macro MAX(a,b) is already defined in minmax.h or
kernel.h before 5.10.

Initially noticed on 6.12, but it now happens after the kernel bump to
6.6.109 as well (upstream commit 6183c65)

In file included from ../mwlwifi-2025.02.06~db97edf2/hif/fwcmd.h:23,
                 from ../mwlwifi-2025.02.06~db97edf2/core.c:25:
../mwlwifi-2025.02.06~db97edf2/hif/hostcmd.h:1124: error: "MAX" redefined [-Werror]
 1124 | #define MAX(a, b) (((a) > (b)) ? (a) : (b))
      |         ^~~
In file included from usr/include/mac80211-backport/linux/minmax.h:4,
                 from ./include/linux/kernel.h:27,
                 from usr/include/mac80211-backport/linux/kernel.h:3,
                 from ./include/linux/skbuff.h:13,
                 from usr/include/mac80211-backport/linux/skbuff.h:3,
                 from ./include/linux/if_ether.h:19,
                 from usr/include/mac80211-backport/linux/if_ether.h:3,
                 from ./include/linux/etherdevice.h:20,
                 from usr/include/mac80211-backport/linux/etherdevice.h:3,
                 from ../mwlwifi-2025.02.06~db97edf2/core.c:18:
./include/linux/minmax.h:315: note: this is the location of the previous definition
  315 | #define MAX(a, b) __cmp(max, a, b)
      |         ^~~

Add a pending upstream patch which replaces the MAX(a,b) macro to avoid
conflicts and allow compilation with 6.12 backports

(cherry picked from commit 822bceb1d12bdb08688051ead06e0c4462e7d123)

Signed-off-by: Stefan Kalscheuer <[email protected]>
Link: https://github.com/openwrt/openwrt/pull/20420
Signed-off-by: Robert Marko <[email protected]>