elf: KeySize of a struct_ops map should always be 4

Signed-off-by: shun159 <[email protected]>

Author: shun159

elf_reader.go

@@ -1477,6 +1477,7 @@ func (ec *elfCode) loadStructOpsMaps() error {
 					Name:       mapName,
 					Type:       StructOpsMap,
 					Key:        &btf.Int{Size: 4},
+					KeySize:    4,
 					Value:      userType,
 					Flags:      flags,
 					MaxEntries: 1,

elf_reader_test.go

@@ -955,6 +955,7 @@ func TestStructOps(t *testing.T) {
 				MaxEntries: 1,
 				Flags:      sys.BPF_F_LINK,
 				Key:        &btf.Int{Size: 4},
+				KeySize:    4,
 				Value: &btf.Struct{
 					Name: "bpf_testmod_ops",
 					Size: 24,