Docs: MSI-HOWTO: Use the subjunctive, and change `can' to `may'

bridges).  In order to ensure that all the data has arrived in memory,

the interrupt handler must read a register on the device which raised

the interrupt.  PCI transaction ordering rules require that all the data

arrives in memory before the value can be returned from the register.

arrive in memory before the value may be returned from the register.

Using MSIs avoids this problem as the interrupt-generating write cannot

pass the data writes, so by the time the interrupt is raised, the driver

knows that all the data has arrived in memory.