drm/amd/pm: Fix warnings

Fixes warnings:

drivers/gpu/drm/amd/amdgpu/../pm/swsmu/smu13/smu_v13_0_6_ppt.c:286:45:
warning: '%s' directive output may be truncated writing up to 29 bytes
into a region of size 23 [-Wformat-truncation=]
drivers/gpu/drm/amd/amdgpu/../pm/swsmu/smu13/smu_v13_0_6_ppt.c:286:52:
warning: '%s' directive output may be truncated writing up to 29 bytes
into a region of size 23 [-Wformat-truncation=]
drivers/gpu/drm/amd/amdgpu/../pm/swsmu/smu14/smu_v14_0.c:72:45: warning:
'%s' directive output may be truncated writing up to 29 bytes into a
region of size 23 [-Wformat-truncation=]
drivers/gpu/drm/amd/amdgpu/../pm/swsmu/smu14/smu_v14_0.c:72:52: warning:
'%s' directive output may be truncated writing up to 29 bytes into a
region of size 23 [-Wformat-truncation=]
Signed-off-by: Lijo Lazar <lijo.lazar@amd.com>
Reviewed-by: Yang Wang <kevinyang.wang@amd.com>
Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

drivers/gpu/drm/amd/pm/swsmu/smu13/smu_v13_0_6_ppt.c

@@ -270,7 +270,7 @@ static int smu_v13_0_6_init_microcode(struct smu_context *smu)
 	struct amdgpu_device *adev = smu->adev;
 	uint32_t p2s_table_id = P2S_TABLE_ID_A;
 	int ret = 0, i, p2stable_count;
-	char ucode_prefix[30];
+	char ucode_prefix[15];
 	char fw_name[30];
 
 	/* No need to load P2S tables in IOV mode */

drivers/gpu/drm/amd/pm/swsmu/smu14/smu_v14_0.c

@@ -57,7 +57,7 @@ int smu_v14_0_init_microcode(struct smu_context *smu)
 {
 	struct amdgpu_device *adev = smu->adev;
 	char fw_name[30];
-	char ucode_prefix[30];
+	char ucode_prefix[15];
 	int err = 0;
 	const struct smc_firmware_header_v1_0 *hdr;
 	const struct common_firmware_header *header;