ACS: Fix incompatible pointer types

[jhunkeler]

See #618

[..]/hstcal/pkg/acs/lib/getacskeys.c:80:61: error: passing argument 5 of ‘GetKeyBool’ makes pointer from integer without a cast [-Wint-conversion]
   80 |         if (GetKeyBool (phdr, "SUBARRAY", NO_DEFAULT, 0, &acs->subarray))
      |                                                          ~~~^~~~~~~~~~
      |                                                             |
      |                                                             int
[..]/hstcal/pkg/acs/lib/getacskeys.c: In function ‘checkACSKeys’:
[..]/hstcal/pkg/acs/lib/getacskeys.c:148:15: error: passing argument 1 of ‘upperCase’ from incompatible pointer type [-Wincompatible-pointer-types]
  148 |     upperCase(&acs->aperture);
      |               ^~~~~~~~~~~~~~
      |               |
      |               char (*)[25]
In file included from [..]/hstcal/pkg/acs/lib/getacskeys.c:11:
[..]/hstcal/include/str_util.h:6:23: note: expected ‘char *’ but argument is of type ‘char (*)[25]’
    6 | void upperCase(char * str);
      |                ~~~~~~~^~~
[..]/hstcal/pkg/acs/lib/getacskeys.c:149:15: error: passing argument 1 of ‘upperCase’ from incompatible pointer type [-Wincompatible-pointer-types]
  149 |     upperCase(&acs->jwrotype);
      |               ^~~~~~~~~~~~~~
      |               |
      |               char (*)[25]
[..]/hstcal/include/str_util.h:6:23: note: expected ‘char *’ but argument is of type ‘char (*)[25]’
    6 | void upperCase(char * str);
      |                ~~~~~~~^~~
[..]/hstcal/pkg/acs/lib/getacskeys.c:150:15: error: passing argument 1 of ‘upperCase’ from incompatible pointer type [-Wincompatible-pointer-types]
  150 |     upperCase(&acs->flashstatus);
      |               ^~~~~~~~~~~~~~~~~
      |               |
      |               char (*)[25]
[..]/hstcal/include/str_util.h:6:23: note: expected ‘char *’ but argument is of type ‘char (*)[25]’
    6 | void upperCase(char * str);
      |                ~~~~~~~^~~
[..]/hstcal/pkg/acs/lib/getacskeys.c:166:19: error: passing argument 1 of ‘upperCase’ from incompatible pointer type [-Wincompatible-pointer-types]
  166 |         upperCase(&acs->ccdamp);
      |                   ^~~~~~~~~~~~
      |                   |
      |                   char (*)[5]
[..]/hstcal/include/str_util.h:6:23: note: expected ‘char *’ but argument is of type ‘char (*)[5]’
    6 | void upperCase(char * str);
      |                ~~~~~~~^~~