MIPS: Cleanup CP0 PRId and CP1 FPIR register access masks

Replace hardcoded CP0 PRId and CP1 FPIR register access masks throughout.
The change does not touch places that use shifted or partial masks.

Signed-off-by: Maciej W. Rozycki <macro@linux-mips.org>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/5838/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
diff --git a/arch/mips/bcm63xx/cpu.c b/arch/mips/bcm63xx/cpu.c
index 7e17374..b713cd6 100644
--- a/arch/mips/bcm63xx/cpu.c
+++ b/arch/mips/bcm63xx/cpu.c
@@ -306,14 +306,14 @@
 
 	switch (c->cputype) {
 	case CPU_BMIPS3300:
-		if ((read_c0_prid() & 0xff00) != PRID_IMP_BMIPS3300_ALT)
+		if ((read_c0_prid() & PRID_IMP_MASK) != PRID_IMP_BMIPS3300_ALT)
 			__cpu_name[cpu] = "Broadcom BCM6338";
 		/* fall-through */
 	case CPU_BMIPS32:
 		chipid_reg = BCM_6345_PERF_BASE;
 		break;
 	case CPU_BMIPS4350:
-		switch ((read_c0_prid() & 0xff)) {
+		switch ((read_c0_prid() & PRID_REV_MASK)) {
 		case 0x04:
 			chipid_reg = BCM_3368_PERF_BASE;
 			break;