powerpc/64: Drop IPI_PRIORITY from asm-offsets
The last use of IPI_PRIORITY in asm was removed in commit 37f55d30df2e
("KVM: PPC: Book3S HV: Convert kvmppc_read_intr to a C function").
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://patch.msgid.link/20241009051701.132282-1-mpe@ellerman.id.au