Some more IWYU fixes

I should have scrolled to the end before uploading.

Change-Id: Ib216ad1557d59405578615367fd31105f10e879e
Reviewed-on: https://boringssl-review.googlesource.com/c/boringssl/+/78767
Commit-Queue: Adam Langley <agl@google.com>
Reviewed-by: Adam Langley <agl@google.com>
Auto-Submit: David Benjamin <davidben@google.com>

crypto/pkcs7/pkcs7_test.cc

diff --git a/crypto/pkcs7/pkcs7_test.cc b/crypto/pkcs7/pkcs7_test.cc
index 6b450c3..89987a8 100644
--- a/crypto/pkcs7/pkcs7_test.cc
+++ b/crypto/pkcs7/pkcs7_test.cc
@@ -23,6 +23,8 @@
 #include <openssl/stack.h>
 #include <openssl/x509.h>
 
+#include <string>
+
 #include "../internal.h"
 #include "../test/test_data.h"
 #include "../test/test_util.h"

crypto/pkcs7/pkcs7_x509.cc

diff --git a/crypto/pkcs7/pkcs7_x509.cc b/crypto/pkcs7/pkcs7_x509.cc
index e18c4a5..d762da1 100644
--- a/crypto/pkcs7/pkcs7_x509.cc
+++ b/crypto/pkcs7/pkcs7_x509.cc
@@ -17,9 +17,12 @@
 #include <assert.h>
 #include <limits.h>
 
+#include <openssl/asn1.h>
 #include <openssl/bytestring.h>
 #include <openssl/cms.h>
+#include <openssl/digest.h>
 #include <openssl/err.h>
+#include <openssl/evp.h>
 #include <openssl/mem.h>
 #include <openssl/obj.h>
 #include <openssl/pem.h>

crypto/x509/x_x509.cc

diff --git a/crypto/x509/x_x509.cc b/crypto/x509/x_x509.cc
index feef072..485231f 100644
--- a/crypto/x509/x_x509.cc
+++ b/crypto/x509/x_x509.cc
@@ -17,6 +17,7 @@
 #include <stdio.h>
 
 #include <openssl/asn1t.h>
+#include <openssl/bytestring.h>
 #include <openssl/evp.h>
 #include <openssl/mem.h>
 #include <openssl/obj.h>