protobuf: Update from 3.6.0.1 -> 3.6.1

Update recipe for protobuf to 3.6.1:

2018-07-27 version 3.6.1 (C++/Java/Python/PHP/Objective-C/C#/Ruby/JavaScript)
  C++
  * Introduced workaround for Windows issue with std::atomic and std::once_flag
    initialization (#4777, #4773).
  PHP
  * Added compatibility with PHP 7.3 (#4898).
  Ruby
  * Fixed Ruby crash involving Any encoding (#4718).

More details available at:
  https://github.com/protocolbuffers/protobuf/compare/v3.6.0.1...v3.6.1

Signed-off-by: Jens Rehsack <sno@netbsd.org>
Signed-off-by: Khem Raj <raj.khem@gmail.com>

meta-oe/recipes-devtools/protobuf/protobuf_3.6.1.bb

@@ -12,7 +12,7 @@ DEPENDS_append_class-target = " protobuf-native"
 
 PV .= "+git${SRCPV}"
 
-SRCREV = "ce044817c7ba0aea27c3fd8e496635d94d20a755"
+SRCREV = "48cb18e5c419ddd23d9badcfe4e9df7bde1979b2"
 
 SRC_URI = "git://github.com/google/protobuf.git;branch=3.6.x \
            file://run-ptest \