gcc 11.1 is around, gcc 10.2 is the default version, so drop
8.4 in order to reduce the gcc choice.
For PowerPC SPE, introduce BR2_GCC_VERSION_POWERPC_SPE
to avoid removing defconfigs arcturus_ucp1020_defconfig,
freescale_p1025twr_defconfig and qemu_ppc_mpc8544ds_defconfig
that are still used by some users [1].
BR2_GCC_VERSION_POWERPC_SPE use the same gcc version (8.4), no
change expected.
[1] 96e80ad214
Signed-off-by: Romain Naour <romain.naour@gmail.com>
Cc: Oleksandr Zhadan <oleks@arcturusnetworks.com>
Cc: Michael Durrant <mdurrant@ArcturusNetworks.com>
Cc: Matthew Weber <matthew.weber@collins.com>
Cc: Thomas Petazzoni <thomas.petazzoni@bootlin.com>
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@bootlin.com>
531b2a10cd