unistr/u{8, 16, 32}-strtok tests: Fix -Wanalyzer-allocation-size warnings

[Bruno Haible]

These two warnings

unistr/test-u-strtok.h:54:28: warning: allocated buffer size is not a multiple 
of the pointee's size [CWE-131] [-Wanalyzer-allocation-size]
unistr/test-u-strtok.h:56:28: warning: allocated buffer size is not a multiple 
of the pointee's size [CWE-131] [-Wanalyzer-allocation-size]

point to a real problem: confusion between 'UNIT *' and 'char *'. Fixed like
this:


2023-09-04  Bruno Haible  <br...@clisp.org>

        unistr/u{8,16,32}-strtok tests: Fix -Wanalyzer-allocation-size warnings.
        * tests/unistr/test-u-strtok.h (test_u_strtok): Correct values of
        input_len and delim_len.

diff --git a/tests/unistr/test-u-strtok.h b/tests/unistr/test-u-strtok.h
index a156d58d24..c7da3d4027 100644
--- a/tests/unistr/test-u-strtok.h
+++ b/tests/unistr/test-u-strtok.h
@@ -50,10 +50,12 @@ test_u_strtok (void)
         'A', 'B', 'C', 'D', 'A', 'B', 'C', 'D', 'A', 'B', 'D', 'E', 0
       };
     ucs4_t u_delim[] = { 0x3000, 0x3001, 0 };
-    size_t input_len = 6 * SIZEOF (u_input);
-    UNIT *input = (UNIT *) malloc (input_len);
-    size_t delim_len = 6 * SIZEOF (u_delim);
-    UNIT *delim = (UNIT *) malloc (delim_len);
+    /* Convert ucs4_t[] to UNIT[].
+       Every ucs4_t yields at most 4 / sizeof (UNIT) units.  */
+    size_t input_len = SIZEOF (u_input) * (4 / sizeof (UNIT));
+    UNIT *input = (UNIT *) malloc (input_len * sizeof (UNIT));
+    size_t delim_len = SIZEOF (u_delim) * (4 / sizeof (UNIT));
+    UNIT *delim = (UNIT *) malloc (delim_len * sizeof (UNIT));
     UNIT *state;
     const UNIT *result;
     UNIT *ptr, *first_ptr, *second_ptr;