Fix test watchpoint_error when run with a 32-bit build of rr.

[bernhardu]

Looks like a 32-bit rr can provide even less hardware breakpionts.

Another option to "fix" would be just skipping it with skip_if_rr_32_bit?

What do you think?

Example output of a failed test:

(rr) break main
break main
Breakpoint 1 at 0x5656328b: file /home/bernhard/data/entwicklung/2023/rr/2022-09-11/rr/src/test/x86/watchpoint_error.c, line 8.
(rr) continue
continue
Continuing.

Breakpoint 1, main ()
    at /home/bernhard/data/entwicklung/2023/rr/2022-09-11/rr/src/test/x86/watchpoint_error.c:8
8         atomic_puts("EXIT-SUCCESS");
watch -l *(long long*)(&buffer[0])
(rr) watch -l *(long long*)(&buffer[0])
Hardware watchpoint 2: -location *(long long*)(&buffer[0])
watch -l *(long long*)(&buffer[8])
(rr) watch -l *(long long*)(&buffer[8])
Hardware watchpoint 3: -location *(long long*)(&buffer[8])
(rr) watch -l *(long long*)(&buffer[16])
watch -l *(long long*)(&buffer[16])
Hardware watchpoint 4: -location *(long long*)(&buffer[16])
watch -l *(long long*)(&buffer[24])
(rr) watch -l *(long long*)(&buffer[24])
Hardware watchpoint 5: -location *(long long*)(&buffer[24])
watch -l *(long long*)(&buffer[32])
(rr) watch -l *(long long*)(&buffer[32])
Hardware watchpoint 6: -location *(long long*)(&buffer[32])
stepi
(rr) stepi
Warning:
Could not insert hardware watchpoint 4.
Could not insert hardware watchpoint 5.
Could not insert hardware watchpoint 6.
Could not insert hardware breakpoints:
You may have requested too many hardware breakpoints/watchpoints.

delete 6
delete 5
watch -l *(long long*)(&buffer[24])
break atomic_puts
Command aborted.
(rr) delete 6
delete 5
(rr) delete 5
watch -l *(long long*)(&buffer[24])
(rr) watch -l *(long long*)(&buffer[24])
Hardware watchpoint 7: -location *(long long*)(&buffer[24])
(rr) break atomic_puts
Breakpoint 8 at 0x56563213: file /home/bernhard/data/entwicklung/2023/rr/2022-09-11/rr/src/test/x86/../util.h, line 178.
(rr) continue
continue
Continuing.
Warning:
Could not insert hardware watchpoint 4.
Could not insert hardware watchpoint 7.
Could not insert hardware breakpoints:
You may have requested too many hardware breakpoints/watchpoints.

Command aborted.
(rr)