Revert "Use inline keyword without underscores consistently"

This reverts commit 58f06e11122723d68c5cb393aeb4ed1c7a2e7bfe.

Bare `inline` is not ANSI C compatible, and NDK users may be using
that.

Test: treehugger
Change-Id: I82c5424522142001cd59da63ef3fd440014451ad
diff --git a/libc/bionic/sys_statvfs.cpp b/libc/bionic/sys_statvfs.cpp
index 3a05c3f..b3a0aca 100644
--- a/libc/bionic/sys_statvfs.cpp
+++ b/libc/bionic/sys_statvfs.cpp
@@ -17,7 +17,7 @@
 #include <sys/statfs.h>
 #include <sys/statvfs.h>
 
-static inline void __bionic_statfs_to_statvfs(const struct statfs* src, struct statvfs* dst) {
+static __inline void __bionic_statfs_to_statvfs(const struct statfs* src, struct statvfs* dst) {
   dst->f_bsize = src->f_bsize;
   dst->f_frsize = src->f_frsize;
   dst->f_blocks = src->f_blocks;