fwlib: fix errors with -Wmissing-prototypes

When the fwlib is built with -Wmissing-prototypes and -Werror
there build breakages that occur. Fix these errors by either
including the header file with the correct declaration or provide
the declaration at the top of the c files for global symbols that
are used by tests.

BUG=chrome-os-partner:17695
BRANCH=None
TEST=built fwlib library with -Wmissing-prototypes and -Werror. Also
     'make runtests' still passes.

Change-Id: I992516ee2545509054887173bc65234905381e06
Signed-off-by: Aaron Durbin
Reviewed-on: https://gerrit.chromium.org/gerrit/44042
Reviewed-by: Bill Richardson <wfrichar@chromium.org>
Commit-Queue: Aaron Durbin <adurbin@chromium.org>
Tested-by: Aaron Durbin <adurbin@chromium.org>
Reviewed-by: Randall Spangler <rspangler@chromium.org>

firmware/lib/include/vboot_kernel.h

@@ -12,7 +12,6 @@
 #include "cgptlib.h"
 #include "load_firmware_fw.h"
 #include "vboot_api.h"
-#include "vboot_kernel.h"
 
 /**
  * Allocate and read GPT data from the drive.  The sector_bytes and

firmware/lib/rollback_index.c

@@ -17,6 +17,15 @@
 #define offsetof(A,B) __builtin_offsetof(A,B)
 #endif
 
+/*
+ * Provide protoypes for functions not in the header file. These prototypes
+ * fix -Wmissing-prototypes warnings.
+ */
+uint32_t ReadSpaceFirmware(RollbackSpaceFirmware *rsf);
+uint32_t WriteSpaceFirmware(RollbackSpaceFirmware *rsf);
+uint32_t ReadSpaceKernel(RollbackSpaceKernel *rsk);
+uint32_t WriteSpaceKernel(RollbackSpaceKernel *rsk);
+
 #ifdef FOR_TEST
 /*
  * Compiling for unit test, so we need the real implementations of

firmware/lib/tpm_bootmode.c

@@ -96,7 +96,8 @@ const uint8_t kBootInvalidSHA1Digest[] = {
  * Given the boot state, return the correct SHA1 digest index for TPMExtend
  * in kBootStateSHA1Digests[].
  */
-int GetBootStateIndex(int dev_mode, int rec_mode, uint64_t keyblock_flags)
+static int GetBootStateIndex(int dev_mode, int rec_mode,
+                             uint64_t keyblock_flags)
 {
 	int index = 0;
 

firmware/lib/vboot_api_kernel.c

@@ -13,6 +13,7 @@
 #include "vboot_audio.h"
 #include "vboot_common.h"
 #include "vboot_display.h"
+#include "vboot_kernel.h"
 #include "vboot_nvstorage.h"
 
 /* Global variables */