tccpp: no cache for include if #elif seen

#ifndef guards are cached, however after #elif on the
same level, the file must be re-read.

Also: preprocess asm as such even when there is no
assembler (arm).

libtcc.c

@@ -1334,13 +1334,11 @@ ST_FUNC int tcc_add_file_internal(TCCState *s1, const char *filename, int flags)
             tcc_strdup(filename));
 
     parse_flags = 0;
-#ifdef CONFIG_TCC_ASM
     /* if .S file, define __ASSEMBLER__ like gcc does */
     if (filetype == AFF_TYPE_ASM || filetype == AFF_TYPE_ASMPP) {
         tcc_define_symbol(s1, "__ASSEMBLER__", NULL);
         parse_flags = PARSE_FLAG_ASM_FILE;
     }
-#endif
 
     if (flags & AFF_PREPROCESS) {
         ret = tcc_preprocess(s1);