fix(riscv/interrupts): call generic IRQC function for sending IPIs

When using IMSIC, IPIs are sent through direct MSI write in the
interrupt file of the target hart. The path through OpenSBI
(sbi_send_ipi) is not suitable since SUPERVISOR SOFTWARE INTERRUPTS
(SSI) are not enabled in this scenario.

By using the generic irqc_send_ipi() function, the IPI sending process
is handled correctly in all the possible configurations (PLIC, APLIC,
IMSIC).

Signed-off-by: Filippo Fontana <[email protected]>

Author: filippofontana

src/arch/riscv/interrupts.c

@@ -47,7 +47,7 @@ void interrupts_arch_ipi_send(cpuid_t target_cpu, irqid_t ipi_id)
     if (USE_ACLINT_IPI()) {
         aclint_send_ipi(target_cpu);
     } else {
-        sbi_send_ipi(1UL << target_cpu, 0);
+        irqc_send_ipi(target_cpu, ipi_id);
     }
 }