Remove unapplied BRCM_TRACING option from Rockchip kernel config

The Rockchip config contained BRCM_TRACING option which had no effect without
TRACING enabled. The option now depends on that option since [1], resulting in
warning in our config checker.

[1] https://lore.kernel.org/lkml/81a29b15eaacc1ac1fb421bdace9ac0c3385f40f.1727179742.git.geert@linux-m68k.org/

buildroot-external/kernel/v6.6.y/kernel-arm64-rockchip.config

@@ -1284,7 +1284,6 @@ CONFIG_BRCMSMAC=m
 CONFIG_BRCMFMAC=m
 CONFIG_BRCMFMAC_USB=y
 CONFIG_BRCMFMAC_PCIE=y
-CONFIG_BRCM_TRACING=y
 CONFIG_BRCMDBG=y
 CONFIG_IPW2100=m
 CONFIG_IPW2100_MONITOR=y