Fix harmless if statements with empty body, spotted by clang

These clang errors are harmless but worth fixing:
  CC    libhw64/fdc.o
/src/qemu/hw/fdc.c:998:74: error: if statement has empty body [-Wempty-body]
        FLOPPY_DPRINTF("Floppy digital input register: 0x%02x\n", retval);
  CC    libhw64/cuda.o
/src/qemu/hw/cuda.c:320:66: error: if statement has empty body [-Wempty-body]
        CUDA_DPRINTF("read: reg=0x%x val=%02x\n", (int)addr, val);
Signed-off-by: NBlue Swirl <blauwirbel@gmail.com>

hw/cuda.c

@@ -316,8 +316,10 @@ static uint32_t cuda_readb(void *opaque, target_phys_addr_t addr)
         val = s->anh;
         break;
     }
-    if (addr != 13 || val != 0)
+    if (addr != 13 || val != 0) {
         CUDA_DPRINTF("read: reg=0x%x val=%02x\n", (int)addr, val);
+    }
+
     return val;
 }
 

hw/fdc.c

@@ -994,8 +994,9 @@ static uint32_t fdctrl_read_dir(FDCtrl *fdctrl)
 #endif
         )
         retval |= FD_DIR_DSKCHG;
-    if (retval != 0)
+    if (retval != 0) {
         FLOPPY_DPRINTF("Floppy digital input register: 0x%02x\n", retval);
+    }
 
     return retval;
 }