configure: fix libuuid test

[ArsenArsen]

&data, where data is a uuid_t, results in a unsigned char*, but uuid_t needs to be passed as unsigned char (*)[16], which is a distinct type. This causes configure to spuriously fail to detect libuuid:

conftest.c: In function 'main':
conftest.c:74:26: error: passing argument 1 of 'uuid_clear' from incompatible pointer type [-Wincompatible-pointer-types]
   74 |  uuid_t data; uuid_clear(&data);
      |                          ^~~~~
      |                          |
      |                          unsigned char (*)[16]
In file included from conftest.c:70:
/usr/include/uuid/uuid.h:85:31: note: expected 'unsigned char *' but argument is of type 'unsigned char (*)[16]'
   85 | extern void uuid_clear(uuid_t uu);
      |                        ~~~~~~~^~
configure:17809: $? = 1