scripts: modpost: check memory allocation results

Fix missing error check for memory allocation functions in
scripts/mod/modpost.c.

Fixes kernel bugzilla #200319:
https://bugzilla.kernel.org/show_bug.cgi?id=200319

Signed-off-by: Randy Dunlap <[e-mail]>
Cc: Yuexing Wang <[e-mail]>
Signed-off-by: Masahiro Yamada <[e-mail]>

scripts/mod/modpost.c

···
 			if (ELF_ST_TYPE(sym->st_info) == STT_SPARC_REGISTER)
 				break;
 			if (symname[0] == '.') {
-				char *munged = strdup(symname);
+				char *munged = NOFAIL(strdup(symname));
 				munged[0] = '_';
 				munged[1] = toupper(munged[1]);
 				symname = munged;
···
 static char *sec2annotation(const char *s)
 {
 	if (match(s, init_exit_sections)) {
-		char *p = malloc(20);
+		char *p = NOFAIL(malloc(20));
 		char *r = p;
 
 		*p++ = '_';
···
 			strcat(p, " ");
 		return r;
 	} else {
-		return strdup("");
+		return NOFAIL(strdup(""));
 	}
 }
 
···
 {
 	if (buf->size - buf->pos < len) {
 		buf->size += len + SZ;
-		buf->p = realloc(buf->p, buf->size);
+		buf->p = NOFAIL(realloc(buf->p, buf->size));
 	}
 	strncpy(buf->p + buf->pos, s, len);
 	buf->pos += len;