add new classifier result

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diff --git a/results/classifier/105/instruction/493 b/results/classifier/105/instruction/493
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+instruction: 0.857
+graphic: 0.849
+device: 0.810
+semantic: 0.644
+vnc: 0.466
+other: 0.461
+socket: 0.369
+mistranslation: 0.368
+network: 0.353
+boot: 0.272
+assembly: 0.130
+KVM: 0.064
+
+RISC-V: Setting mtimecmp to -1 immediately triggers an interrupt
+Description of problem:
+When setting mtimecmp to -1, which should set a timer infinitely far in the future, a timer interrupt is triggered immediately. This happens for most values over 2^61. It is the same for both 32-bit and 64-bit, and for M-mode writing to mtimecmp directly and S-mode using OpenSBI.
+
+I have looked through the source code, and the problem is in the function `sifive_clint_write_mtimecmp`, in the file `/hw/intc/sifive_clint.c`. First, the muldiv64 multiplies diff with 100, causing an overflow (at least for -M virt, other machines might use a different timebase_freq). Then, the unsigned `next` is passed to `timer_mod`, which takes a signed integer. In `timer_mod_ns_locked` the value is set to `MAX(next, 0)`, which means that if the MSB of `next` was set, the interrupt happens immediately. This means that it is impossible to set timers more than 2^63 nanoseconds in the future.
+
+This problem basically only affects programs which disable timer interrupts by setting the next one infinitely far in the future. However, the SBI doc specifically says that this is a valid approach, so it should be supported. Using the MSB doesn't work without changing code functionality in QEMU, but it should be sufficient to cap `next` at the maximum signed value.