Move assembly source prototypes from xtensa_ksyms.c to asm/asm-prototypes.h, move corresponding EXPORT_SYMBOLs to the assembly sources and enable HAVE_ASM_MODVERSIONS for xtensa. Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
Don't rely on libgcc presence, build own versions of the helpers with correct ABI. Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>