Revert "system properties: doubling the shared file size to 256Kb"

This reverts commit 46cce489954d0fe3b142802c41539e4bf8888397.

Reason for revert: 

Will put a change behind flags to bump storage to 1Mb for internal build only. AOSP code does not need to be changed. The change will be only made to git_main.

Change-Id: If3484d0e56f4c3d8fc729f55744c2d8ebdd13b11
diff --git a/libc/system_properties/prop_area.cpp b/libc/system_properties/prop_area.cpp
index d5693b9..4668eed 100644
--- a/libc/system_properties/prop_area.cpp
+++ b/libc/system_properties/prop_area.cpp
@@ -41,7 +41,7 @@
 
 #include <async_safe/log.h>
 
-constexpr size_t PA_SIZE = 256 * 1024;
+constexpr size_t PA_SIZE = 128 * 1024;
 constexpr uint32_t PROP_AREA_MAGIC = 0x504f5250;
 constexpr uint32_t PROP_AREA_VERSION = 0xfc6ed0ab;