[S] Change in coreboot[main]: arch/arm64/arch_timer: Fix possible overflow in multiplication

[Paul Menzel (Code Review)]

Attention is currently required from: Julius Werner, Yidi Lin, Yu-Ping Wu.

Paul Menzel has posted comments on this change. ( https://review.coreboot.org/c/coreboot/+/78800?usp=email )

Change subject: arch/arm64/arch_timer: Fix possible overflow in multiplication
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Patch Set 2:

(1 comment)

File src/arch/arm64/arch_timer.c:

https://review.coreboot.org/c/coreboot/+/78800/comment/a71a194a_06da4a16 :
PS2, Line 11: static uint32_t tfreq, mult;
            : 	uint32_t div;
            : 
            : 	if (tfreq == 0) {
            : 		tfreq = raw_read_cntfrq_el0();
            : 		assert(tfreq > 0)
            : 		mult = 1000000;
            : 		div = gcd(mult, tfreq);
            : 		tfreq /= div;
            : 		mult /= div;
            : 	}
            : 
            : 	long usecs = (tvalue * mult) / tfreq;
Nice, but why not just cast `tvalue`, and let the compiler figure out the rest? Is that possible?