[REFACTOR] Hafnium style: capitalize CPU, vCPU, and VM.

Change-Id: I6090deee0f52737653f5b18c09a1c64cadd38c8c
diff --git a/inc/hf/arch/cpu.h b/inc/hf/arch/cpu.h
index ac93c4c..a7fe5a8 100644
--- a/inc/hf/arch/cpu.h
+++ b/inc/hf/arch/cpu.h
@@ -34,7 +34,7 @@
 void arch_regs_reset(struct vcpu *vcpu);
 
 /**
- * Updates the given registers so that when a vcpu runs, it starts off at the
+ * Updates the given registers so that when a vCPU runs, it starts off at the
  * given address (pc) with the given argument.
  *
  * This function must only be called on an arch_regs that is known not be in use