Cleanup unused dependency to libprocessgroup

Bug: http://b/197965342

Dependence on libprocessgroup was removed in aosp/947297

Test: presubmit
Change-Id: I802efee3500e25006b55e0f35cb8650fd1aa2033
diff --git a/libbpf_android/Android.bp b/libbpf_android/Android.bp
index 06528c8..e305cc9 100644
--- a/libbpf_android/Android.bp
+++ b/libbpf_android/Android.bp
@@ -58,7 +58,6 @@
     shared_libs: [
         "libbase",
         "libutils",
-        "libprocessgroup",
         "liblog",
         "libbpf",
     ],
diff --git a/libbpf_android/BpfUtils.cpp b/libbpf_android/BpfUtils.cpp
index 8689192..414b7b2 100644
--- a/libbpf_android/BpfUtils.cpp
+++ b/libbpf_android/BpfUtils.cpp
@@ -36,7 +36,6 @@
 
 #include <android-base/unique_fd.h>
 #include <log/log.h>
-#include <processgroup/processgroup.h>
 
 using android::base::unique_fd;