configs/qemu_ppc64*: remove binutils version from defconfigs

Buildroot 2022.05 use binutils 2.37 by default, but the binutils
version was downgraded to the previous binutils version in qemu_ppc64*
defconfigs due to a bug in binutils 2.37 [1].

Later when binutils 2.36 has been removed the binutils version has
been updated to 2.38 (even though it was already the default version
selected by Buildroot at that time) [2].

Since then, several binutils release has been added and the binutils
version 2.38 has been removed recently [3].

Since the initial bug is gone with the removal of binutils 2.37,
we can safely remove the binutils version from qemu_ppc64 defconfigs.

[1] 1e2fe860f3
[2] e461c9adc8
[3] 1391c99d62

Fixes:
https://gitlab.com/buildroot.org/toolchains-builder/-/jobs/4798047373

Signed-off-by: Romain Naour <romain.naour@gmail.com>
Cc: Cédric Le Goater <clg@kaod.org>
Cc: Joel Stanley <joel@jms.id.au>
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@bootlin.com>

configs/qemu_ppc64_e5500_defconfig

@@ -3,7 +3,6 @@ BR2_powerpc64=y
 BR2_powerpc_e5500=y
 
 # System
-BR2_BINUTILS_VERSION_2_38_X=y
 BR2_SYSTEM_DHCP="eth0"
 BR2_TARGET_GENERIC_GETTY_PORT="ttyS0"
 

configs/qemu_ppc64_pseries_defconfig

@@ -3,7 +3,6 @@ BR2_powerpc64=y
 BR2_powerpc_power7=y
 
 # System
-BR2_BINUTILS_VERSION_2_38_X=y
 BR2_SYSTEM_DHCP="eth0"
 BR2_TARGET_GENERIC_GETTY_PORT="hvc0"
 

configs/qemu_ppc64le_powernv8_defconfig

@@ -3,7 +3,6 @@ BR2_powerpc64le=y
 BR2_powerpc_power8=y
 
 # System
-BR2_BINUTILS_VERSION_2_38_X=y
 BR2_TARGET_GENERIC_GETTY_PORT="hvc0"
 BR2_SYSTEM_DHCP="eth0"
 

configs/qemu_ppc64le_pseries_defconfig

@@ -3,7 +3,6 @@ BR2_powerpc64le=y
 BR2_powerpc_power8=y
 
 # System
-BR2_BINUTILS_VERSION_2_38_X=y
 BR2_TARGET_GENERIC_GETTY_PORT="hvc0"
 BR2_SYSTEM_DHCP="eth0"