libuuid/src/gen_uuid.c: fix cs_min declaration

libuuid/src/gen_uuid.c: fix cs_min declaration

Define cs_min through a define and not a const int to avoid the
following build failure with -O0 raised since version 2.39 and
https://github.com/util-linux/util-linux/commit/2fa4168c8bc9d5438bc1dfadda293c7c21b6fa59:

libuuid/src/gen_uuid.c: In function 'uuid_generate_time_generic':
libuuid/src/gen_uuid.c:536:33: error: initializer element is not constant
  THREAD_LOCAL int  cache_size = cs_min;
                                 ^~~~~~

For consistency, also use define for cs_max and cs_factor

Fixes:
 - http://autobuild.buildroot.org/results/2f80a5cdb523cc3c8c0f3693607a1be036b2ae98

Signed-off-by: Fabrice Fontaine <fontaine.fabrice@gmail.com>