configs/qemu_ppc64*: bump to binutils-2.38

Commit 1e2fe860f3a2 (configs/qemu_ppc64*: downgrade binutils to 2.36.1).
Since then, we've dropped support for binutios 2.36, and hte default is
2.38.x, which has the required changes to fix:
    https://github.com/linuxppc/issues/issues/388

Pin the qemu-ppc64 defconfig to explicitly use binutils 2.38.x

Signed-off-by: Cédric Le Goater <clg@kaod.org>
[yann.morin.1998@free.fr:
  - explictily force binutils 2.38
  - reword commit log to explain why
  - reword commit log: it's not really a revert
]
Signed-off-by: Yann E. MORIN <yann.morin.1998@free.fr>

configs/qemu_ppc64_e5500_defconfig

@@ -3,7 +3,7 @@ BR2_powerpc64=y
 BR2_powerpc_e5500=y
 
 # System
-BR2_BINUTILS_VERSION_2_36_X=y
+BR2_BINUTILS_VERSION_2_38_X=y
 BR2_SYSTEM_DHCP="eth0"
 BR2_TARGET_GENERIC_GETTY_PORT="ttyS0"
 

configs/qemu_ppc64_pseries_defconfig

@@ -3,7 +3,7 @@ BR2_powerpc64=y
 BR2_powerpc_power7=y
 
 # System
-BR2_BINUTILS_VERSION_2_36_X=y
+BR2_BINUTILS_VERSION_2_38_X=y
 BR2_SYSTEM_DHCP="eth0"
 BR2_TARGET_GENERIC_GETTY_PORT="hvc0"
 

configs/qemu_ppc64le_powernv8_defconfig

@@ -3,7 +3,7 @@ BR2_powerpc64le=y
 BR2_powerpc_power8=y
 
 # System
-BR2_BINUTILS_VERSION_2_36_X=y
+BR2_BINUTILS_VERSION_2_38_X=y
 BR2_TARGET_GENERIC_GETTY_PORT="hvc0"
 BR2_SYSTEM_DHCP="eth0"
 

configs/qemu_ppc64le_pseries_defconfig

@@ -3,7 +3,7 @@ BR2_powerpc64le=y
 BR2_powerpc_power8=y
 
 # System
-BR2_BINUTILS_VERSION_2_36_X=y
+BR2_BINUTILS_VERSION_2_38_X=y
 BR2_TARGET_GENERIC_GETTY_PORT="hvc0"
 BR2_SYSTEM_DHCP="eth0"