powerpc/kernel: Rename PACA_DSCR to PACA_DSCR_DEFAULT

PACA_DSCR offset macro tracks dscr_default element in the paca
structure. Better change the name of this macro to match that of the
data element it tracks. Makes the code more readable.

Signed-off-by: Anshuman Khandual <khandual@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

arch/powerpc/kvm/book3s_hv_rmhandlers.S

@@ -324,7 +324,7 @@ kvm_start_guest:
 kvm_secondary_got_guest:
 
 	/* Set HSTATE_DSCR(r13) to something sensible */
-	ld	r6, PACA_DSCR(r13)
+	ld	r6, PACA_DSCR_DEFAULT(r13)
 	std	r6, HSTATE_DSCR(r13)
 
 	/* Order load of vcore, ptid etc. after load of vcpu */