Revert "Pull the pthread_key_t functions out of pthread.c."

This reverts commit ad59322ae432d11ff36dcf046016af8cfe45fbe4

somehow my unfinished libm/Android.mk change got into here.

Change-Id: I46be626c5269d60fb1ced9862f2ebaa380b4e0af
diff --git a/libc/Android.mk b/libc/Android.mk
index d21878a..c7828cf 100644
--- a/libc/Android.mk
+++ b/libc/Android.mk
@@ -406,8 +406,7 @@
 	bionic/ptrace.c.arm
 
 libc_static_common_src_files += \
-    bionic/pthread.c.arm \
-    bionic/pthread_key.cpp.arm \
+        bionic/pthread.c.arm \
 
 # these are used by the static and dynamic versions of the libc
 # respectively
@@ -447,8 +446,7 @@
 	bionic/ptrace.c
 
 libc_static_common_src_files += \
-    bionic/pthread.c \
-    bionic/pthread_key.cpp \
+        bionic/pthread.c \
 
 libc_arch_static_src_files := \
 	bionic/dl_iterate_phdr_static.c
@@ -494,8 +492,7 @@
 	bionic/ptrace.c
 
 libc_static_common_src_files += \
-    bionic/pthread.c
-    bionic/pthread_key.cpp \
+	bionic/pthread.c
 
 libc_arch_static_src_files := \
 	bionic/dl_iterate_phdr_static.c