kernel: strip unnecessary symbol table information from kernel modules

reduces default squashfs size on ar71xx by about 4k

lede-commit: 058d331a39077f159ca8922f1f422a1346d6aa67
Signed-off-by: Felix Fietkau <nbd@nbd.name>

Makefile

@@ -403,8 +403,7 @@ KBUILD_AFLAGS_KERNEL :=
 KBUILD_CFLAGS_KERNEL :=
 KBUILD_AFLAGS_MODULE  := -DMODULE
 KBUILD_CFLAGS_MODULE  := -DMODULE
-KBUILD_LDFLAGS_MODULE := -T $(srctree)/scripts/module-common.lds
-GCC_PLUGINS_CFLAGS :=
+KBUILD_LDFLAGS_MODULE = -T $(srctree)/scripts/module-common.lds $(if $(CONFIG_PROFILING),,-s)
 
 # Read KERNELRELEASE from include/config/kernel.release (if it exists)
 KERNELRELEASE = $(shell cat include/config/kernel.release 2> /dev/null)