tpm: Add "static" declaration to functions not used outside tcgbios.c

Signed-off-by: Kevin O'Connor <kevin@koconnor.net>
diff --git a/src/tcgbios.c b/src/tcgbios.c
index 5229b4e..341ab9d 100644
--- a/src/tcgbios.c
+++ b/src/tcgbios.c
@@ -1136,7 +1136,7 @@
 /*
  * Add event separators for PCRs 0 to 7; specs on 'Measuring Boot Events'
  */
-u32
+static u32
 tpm_add_event_separators(void)
 {
     u32 rc;
@@ -1205,7 +1205,7 @@
 /*
  * Add measurement to the log about option rom scan
  */
-u32
+static u32
 tpm_start_option_rom_scan(void)
 {
     if (!CONFIG_TCGBIOS)
@@ -1248,7 +1248,7 @@
 }
 
 
-u32
+static u32
 tpm_smbios_measure(void)
 {
     if (!CONFIG_TCGBIOS)