tpm: add extra blank lines between declarations and code

Fix following checkpatch.pl issue in TPM-related code:

    WARNING: Missing a blank line after declarations

Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
Reviewed-by: Tom Rini <trini@konsulko.com>
Reviewed-by: Simon Glass <sjg@chromium.org>
diff --git a/lib/tpm.c b/lib/tpm.c
index e743935..899528e 100644
--- a/lib/tpm.c
+++ b/lib/tpm.c
@@ -204,6 +204,7 @@
 static u32 tpm_command_size(const void *command)
 {
 	const size_t command_size_offset = 2;
+
 	return get_unaligned_be32(command + command_size_offset);
 }
 
@@ -216,6 +217,7 @@
 static u32 tpm_return_code(const void *response)
 {
 	const size_t return_code_offset = 6;
+
 	return get_unaligned_be32(response + return_code_offset);
 }
 
@@ -843,6 +845,7 @@
 u32 tpm_end_oiap(void)
 {
 	u32 err = TPM_SUCCESS;
+
 	if (oiap_session.valid)
 		err = tpm_terminate_auth_session(oiap_session.handle);
 	return err;