mem-cache: Remove extra numSets zero check.

numSets is unsigned, so it cannot be lower than 0. Besides, isPowerOf2(0)
is false by definition (and implemmentation*), so there is no need for the
double check.

* As presented in base/intmath.hh

Change-Id: I3f6296694a937434feddc7ed21f11c2a6fdfc5a9
Reviewed-on: https://gem5-review.googlesource.com/7901
Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com>
Reviewed-by: Nikos Nikoleris <nikos.nikoleris@arm.com>
Maintainer: Andreas Sandberg <andreas.sandberg@arm.com>

src/mem/cache/tags/base_set_assoc.cc

@@ -63,7 +63,7 @@ BaseSetAssoc::BaseSetAssoc(const Params *p)
     if (blkSize < 4 || !isPowerOf2(blkSize)) {
         fatal("Block size must be at least 4 and a power of 2");
     }
-    if (numSets <= 0 || !isPowerOf2(numSets)) {
+    if (!isPowerOf2(numSets)) {
         fatal("# of sets must be non-zero and a power of 2");
     }
     if (assoc <= 0) {