Revert "ram: temporarily disable assertion on rIdx out of bound (wait for icache uncache)"

This reverts commit 55e377db.

src/test/csrc/ram.cpp

@@ -215,9 +215,8 @@ void ram_finish() {
 
 extern "C" uint64_t ram_read_helper(uint8_t en, uint64_t rIdx) {
   if (en && rIdx >= RAMSIZE / sizeof(uint64_t)) {
-    printf("WARN: ram rIdx = 0x%lx out of bound!\n", rIdx);
-    // assert(rIdx < RAMSIZE / sizeof(uint64_t));
-    return 0x12345678deadbeafULL;
+    printf("ERROR: ram rIdx = 0x%lx out of bound!\n", rIdx);
+    assert(rIdx < RAMSIZE / sizeof(uint64_t));
   }
   return (en) ? ram[rIdx] : 0;
 }