drm/amd/powerplay: fix boolreturn.cocci warnings

drivers/gpu/drm/amd/amdgpu/../powerplay/hwmgr/tonga_hwmgr.c:2653:9-10: WARNING: return of 0/1 in function 'is_pcie_gen2_supported' with return type bool
drivers/gpu/drm/amd/amdgpu/../powerplay/hwmgr/tonga_hwmgr.c:2645:9-10: WARNING: return of 0/1 in function 'is_pcie_gen3_supported' with return type bool

 Return statements in functions returning bool should use
 true/false instead of 1/0.
Generated by: scripts/coccinelle/misc/boolreturn.cocci

CC: yanyang1 <young.yang@amd.com>
Signed-off-by: NFengguang Wu <fengguang.wu@intel.com>
Signed-off-by: NAlex Deucher <alexander.deucher@amd.com>

drivers/gpu/drm/amd/include/amd_pcie_helpers.h

@@ -28,17 +28,17 @@
 static inline bool is_pcie_gen3_supported(uint32_t pcie_link_speed_cap)
 {
 	if (pcie_link_speed_cap & CAIL_PCIE_LINK_SPEED_SUPPORT_GEN3)
-		return 1;
+		return true;
 
-	return 0;
+	return false;
 }
 
 static inline bool is_pcie_gen2_supported(uint32_t pcie_link_speed_cap)
 {
 	if (pcie_link_speed_cap & CAIL_PCIE_LINK_SPEED_SUPPORT_GEN2)
-		return 1;
+		return true;
 
-	return 0;
+	return false;
 }
 
 /* Get the new PCIE speed given the ASIC PCIE Cap and the NewState's requested PCIE speed*/