vendor._siliconblue: fix off-by-1 with default_clk = "SB_LFOSC".
#3830
| Job | Run time |
|---|---|
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| 1m 3s | |
| 59s | |
| 1m 7s | |
| 45s | |
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| 1m 59s | |
| 2m 43s | |
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| 2m 54s | |
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| 4m 40s | |
| 2m 26s | |
| 7s | |
| 0s | |
| 3s | |
| 19s | |
| 9s | |
| 0s | |
| 39m 57s |