Revert "bcm27xx: bcm27xx: update defconfig"

Revert "bcm27xx: bcm27xx: update defconfig"

This reverts all four commits
dbb45421bab "bcm27xx: bcm2708: update defconfig"
332f69583ad "bcm27xx: bcm2709: update defconfig"
a478202d74b "bcm27xx: bcm2710: update defconfig"
82da1dfd69a "bcm27xx: bcm2711: update defconfig"

this also highlighted an unrelated kconfig failure
that warrants investigation. But for now it is important
for the bcm27xx target to come back again.

|*
|* Restart config...
|*
|*
|* Allow override default queue discipline
|*
|Allow override default queue discipline (NET_SCH_DEFAULT) [Y/n/?] y
|  Default queuing discipline
|    1. Fair Queue (DEFAULT_FQ) (NEW)
|    2. Controlled Delay (DEFAULT_CODEL) (NEW)
|  > 3. Fair Queue Controlled Delay (DEFAULT_FQ_CODEL)
|    4. Stochastic Fair Queue (DEFAULT_SFQ) (NEW)
|    5. Priority FIFO Fast (DEFAULT_PFIFO_FAST)
|  choice[1-5?]:
|Error in reading or end of file.

Signed-off-by: Christian Lamparter <chunkeey@gmail.com>