TPM: increase default TPM buffer

The TPM Working Group requested this communication buffer increase given that a
particular TPM vendor can support a TPM_SHA1Start command input bigger than the
current size.
Signed-off-by: NRajiv Andrade <srajiv@linux.vnet.ibm.com>
Signed-off-by: NJames Morris <jmorris@namei.org>

drivers/char/tpm/tpm.c

@@ -31,7 +31,7 @@
 
 enum tpm_const {
 	TPM_MINOR = 224,	/* officially assigned */
-	TPM_BUFSIZE = 2048,
+	TPM_BUFSIZE = 4096,
 	TPM_NUM_DEVICES = 256,
 };