kernel: add disabled PROC_STRIPPED

Otherwise the missing symbol is added to target config for every kernel
config refresh.

While at it, remove the disabled symbol from target configs.

Fixes: 4943bc5cff ("kernel: only strip proc for small flash devices")
Signed-off-by: Sungbo Eo <mans0n@gorani.run>

target/linux/generic/config-5.4

@@ -4123,6 +4123,7 @@ CONFIG_PRINT_STACK_DEPTH=64
 CONFIG_PROC_FS=y
 # CONFIG_PROC_KCORE is not set
 # CONFIG_PROC_PAGE_MONITOR is not set
+# CONFIG_PROC_STRIPPED is not set
 CONFIG_PROC_SYSCTL=y
 # CONFIG_PROC_VMCORE_DEVICE_DUMP is not set
 # CONFIG_PROFILE_ALL_BRANCHES is not set

target/linux/ipq807x/config-default

@@ -502,7 +502,6 @@ CONFIG_PREEMPT_COUNT=y
 CONFIG_PREEMPT_RCU=y
 CONFIG_PRINTK_TIME=y
 CONFIG_PROC_PAGE_MONITOR=y
-# CONFIG_PROC_STRIPPED is not set
 CONFIG_PTP_1588_CLOCK=y
 CONFIG_PWM=y
 CONFIG_PWM_SYSFS=y

target/linux/rockchip/armv8/config-5.4

@@ -346,7 +346,6 @@ CONFIG_PREEMPT_RCU=y
 CONFIG_PRINTK_TIME=y
 # CONFIG_PRINT_QUOTA_WARNING is not set
 CONFIG_PROC_PAGE_MONITOR=y
-# CONFIG_PROC_STRIPPED is not set
 CONFIG_PROC_VMCORE=y
 CONFIG_PWM=y
 CONFIG_PWM_ROCKCHIP=y

target/linux/zynq/config-5.4

@@ -514,7 +514,6 @@ CONFIG_POWER_RESET_VEXPRESS=y
 CONFIG_POWER_SUPPLY=y
 CONFIG_PPS=y
 CONFIG_PROC_EVENTS=y
-# CONFIG_PROC_STRIPPED is not set
 CONFIG_PTP_1588_CLOCK=y
 CONFIG_R8169=y
 CONFIG_RAS=y