builtin: move C. calls to .c.v files (#11164)

vlib/builtin/builtin.v

@@ -15,26 +15,6 @@ fn on_panic(f fn(int)int) {
 }
 */
 
-// print_backtrace shows a backtrace of the current call stack on stdout
-pub fn print_backtrace() {
-	// At the time of backtrace_symbols_fd call, the C stack would look something like this:
-	// * print_backtrace_skipping_top_frames
-	// * print_backtrace itself
-	// * the rest of the backtrace frames
-	// => top 2 frames should be skipped, since they will not be informative to the developer
-	$if !no_backtrace ? {
-		$if freestanding {
-			println(bare_backtrace())
-		} $else {
-			$if tinyc {
-				C.tcc_backtrace(c'Backtrace')
-			} $else {
-				print_backtrace_skipping_top_frames(2)
-			}
-		}
-	}
-}
-
 struct VCastTypeIndexName {
 	tindex int
 	tname  string