Do not use statements that "fall through"

Addressing:
/home/jcerny/openscap/src/OVAL/probes/independent/sql57_probe.c: In function ‘__clearmem’:
/home/jcerny/openscap/src/OVAL/probes/independent/sql57_probe.c:120:10: warning: this statement may fall through [-Wimplicit-fallthrough=]
     p[2] = (uint8_t)(random() % (1 << 8));
     ~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
/home/jcerny/openscap/src/OVAL/probes/independent/sql57_probe.c:121:4: note: here
    case 2:
    ^~~~
/home/jcerny/openscap/src/OVAL/probes/independent/sql57_probe.c:122:10: warning: this statement may fall through [-Wimplicit-fallthrough=]
     p[1] = (uint8_t)(random() % (1 << 8));
     ~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
/home/jcerny/openscap/src/OVAL/probes/independent/sql57_probe.c:123:4: note: here
    case 1:
    ^~~~

Author: jan-cerny

src/OVAL/probes/independent/sql57.c

@@ -124,13 +124,8 @@ static void __clearmem(void *ptr, int len)
 			register int      l = len % sizeof(uint32_t);
 			register uint8_t *p = (uint8_t *)ptr;
 
-			switch (l) {
-			case 3:
-				p[2] = (uint8_t)(random() % (1 << 8));
-			case 2:
-				p[1] = (uint8_t)(random() % (1 << 8));
-			case 1:
-				p[0] = (uint8_t)(random() % (1 << 8));
+			for (int i = 0; i < l; i++) {
+				p[i] = (uint8_t)(random() % (1 << 8));
 			}
 		} while (0);
 	}