runners: bench: Added BENCH_SIMTIME/SIMRESET/PAUSE/RESUME/etc

- BENCH_SIMTIME()   => lfs3_kiwibd_simtime()
- BENCH_SIMRESET()  => lfs3_kiwibd_simreset()
- BENCH_SIMPAUSE()  => lfs3_kiwibd_simpause()
- BENCH_SIMRESUME() => lfs3_kiwibd_simresume()
- BENCH_RESET()     => lfs3_kiwibd_simreset() + BENCH_STACK/HEAP_RESET()
- BENCH_PAUSE()     => lfs3_kiwibd_simpause() + BENCH_STACK/HEAP_PAUSE()
- BENCH_RESUME()    => lfs3_kiwibd_simresume() + BENCH_STACK/HEAP_RESUME()

This does two things:

1. Adds pause/resume counters to bd counters to make it easier to
   exclude operations from the current bench (potentially useful for
   seq+disk usage).

2. Exposes bd simtime operations as BENCH_* macros, to make it a bit
   easier to interact with simtime without tying all the benches to
   kiwibd. (Not that we'll ever probably not use kiwibd, but still).

Also adopted 32-bit counters for stack/heap pause state instead of a
32-bit stack. Not that either are at a risk of overflowing, but better
safe than sorry.

benches/bench_helpers.c

@@ -10,9 +10,6 @@
 // this writes a 1 block file 2*block_count times to get it into a good
 // state for benchmarking
 int bench_helpers_warmup(lfs3_t *lfs3) {
-    BENCH_STACK_PAUSE();
-    BENCH_HEAP_PAUSE();
-
     uint8_t *wbuf = malloc(BLOCK_SIZE);
     memset(wbuf, '1', BLOCK_SIZE);
 
@@ -29,18 +26,12 @@ int bench_helpers_warmup(lfs3_t *lfs3) {
     lfs3_remove(lfs3, "warmup") => 0;
 
     free(wbuf);
-
-    BENCH_HEAP_RESUME();
-    BENCH_STACK_RESUME();
     return 0;
 }
 
 
 // find tight disk usage
 uintmax_t bench_helpers_usage(lfs3_t *lfs3) {
-    BENCH_STACK_PAUSE();
-    BENCH_HEAP_PAUSE();
-
     // measure disk usage
     //
     // littlefs can be a dag, so build a bitmap to find the exact
@@ -70,9 +61,6 @@ uintmax_t bench_helpers_usage(lfs3_t *lfs3) {
     }
 
     free(usage_bmap);
-
-    BENCH_HEAP_RESUME();
-    BENCH_STACK_RESUME();
     return (uintmax_t)usage * (uintmax_t)BLOCK_SIZE;
 }