bmc: move away from blobs namespace

The blobs namespace is really owned by phosphor-ipmi-blobs.  Move all
phosphor-ipmi-flash objects into ipmi_flash namespace.

Signed-off-by: Patrick Venture <venture@google.com>
Change-Id: I51b721ad4f3cdc4cc43846c942967ed2e5f16589
diff --git a/file_handler.cpp b/file_handler.cpp
index 9fd5ea8..e81730d 100644
--- a/file_handler.cpp
+++ b/file_handler.cpp
@@ -22,7 +22,7 @@
 #include <string>
 #include <vector>
 
-namespace blobs
+namespace ipmi_flash
 {
 namespace fs = std::filesystem;
 
@@ -103,4 +103,4 @@
     return 0;
 }
 
-} // namespace blobs
+} // namespace ipmi_flash