Revert "lantiq: xway: kernel: enable SMP support"

Enabling SMP on the xway target results in two issues:

* some danube chipset-based devices fail on boot,
* on devices based on the arx100 chipset, enabling smp
results in a degradation of NAT performance.

After these two issues are fixed, SMP can be re-enabled.

This reverts commit 084c20f.

Fixes: openwrt#13934
Fixes: openwrt#14283
Signed-off-by: Aleksander Jan Bajkowski <olek2@wp.pl>

target/linux/lantiq/xway/config-5.15

@@ -4,9 +4,6 @@ CONFIG_ARCH_KEEP_MEMBLOCK=y
 CONFIG_AT803X_PHY=y
 CONFIG_BLK_MQ_PCI=y
 CONFIG_CPU_HAS_DIEI=y
-CONFIG_CPU_MIPSR2_IRQ_EI=y
-CONFIG_CPU_MIPSR2_IRQ_VI=y
-CONFIG_CPU_RMAP=y
 CONFIG_CRC16=y
 CONFIG_CRYPTO_DEFLATE=y
 CONFIG_CRYPTO_HASH_INFO=y
@@ -25,11 +22,6 @@ CONFIG_LANTIQ_ETOP=y
 CONFIG_LZO_COMPRESS=y
 CONFIG_LZO_DECOMPRESS=y
 CONFIG_MIPS_EBPF_JIT=y
-CONFIG_MIPS_MT=y
-CONFIG_MIPS_MT_FPAFF=y
-CONFIG_MIPS_MT_SMP=y
-CONFIG_MIPS_NR_CPU_NR_MAP=2
-CONFIG_MIPS_PERF_SHARED_TC_COUNTERS=y
 CONFIG_MTD_NAND_CORE=y
 CONFIG_MTD_NAND_ECC=y
 CONFIG_MTD_NAND_ECC_SW_HAMMING=y
@@ -39,44 +31,26 @@ CONFIG_MTD_UBI=y
 CONFIG_MTD_UBI_BEB_LIMIT=20
 CONFIG_MTD_UBI_BLOCK=y
 CONFIG_MTD_UBI_WL_THRESHOLD=4096
-CONFIG_NET_FLOW_LIMIT=y
 CONFIG_NET_SELFTESTS=y
 CONFIG_NLS=y
-CONFIG_NR_CPUS=2
-CONFIG_PADATA=y
 CONFIG_PCI=y
 CONFIG_PCI_DOMAINS=y
 CONFIG_PCI_LANTIQ=y
 CONFIG_PSB6970_PHY=y
 CONFIG_PTP_1588_CLOCK_OPTIONAL=y
-CONFIG_QUEUED_RWLOCKS=y
-CONFIG_QUEUED_SPINLOCKS=y
 CONFIG_REGULATOR=y
 CONFIG_REGULATOR_FIXED_VOLTAGE=y
-CONFIG_RFS_ACCEL=y
-CONFIG_RPS=y
 CONFIG_RTL8306_PHY=y
 CONFIG_RTL8366RB_PHY=y
 CONFIG_RTL8366_SMI=y
-# CONFIG_SCHED_CORE is not set
-CONFIG_SCHED_SMT=y
 CONFIG_SGL_ALLOC=y
-CONFIG_SMP=y
-CONFIG_SMP_UP=y
-CONFIG_SOCK_RX_QUEUE_MAPPING=y
 CONFIG_SOC_TYPE_XWAY=y
 CONFIG_SOC_XWAY=y
 CONFIG_SWCONFIG=y
-CONFIG_SYNC_R4K=y
-CONFIG_SYS_SUPPORTS_SCHED_SMT=y
-CONFIG_SYS_SUPPORTS_SMP=y
-CONFIG_TREE_RCU=y
-CONFIG_TREE_SRCU=y
 CONFIG_UBIFS_FS=y
 CONFIG_USB=y
 CONFIG_USB_COMMON=y
 CONFIG_USB_SUPPORT=y
-CONFIG_XPS=y
 CONFIG_XXHASH=y
 CONFIG_ZLIB_DEFLATE=y
 CONFIG_ZLIB_INFLATE=y